diff --git a/ChangeLog b/ChangeLog
index ced193454..42dc8d51d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,9 @@
 Version 0.94
 ------------
 
+2008-02-21
+	* removed GTK gui and interface configure options
+
 2008-02-06
 	* added new gui commands and fixed trajectory loading
 
diff --git a/Makefile.am b/Makefile.am
index 5333660f0..f79e3cc54 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 SUBDIRS = src
 
-EXTRA_DIST = scripts/*.txt doc/manual.pdf src/gui-qt/icons/*.svg src/gui-gtk/icons/*/*.xpm data/spgrp.dat data/filters/*
+EXTRA_DIST = scripts/*.txt doc/manual.pdf src/gui/icons/*.svg data/spgrp.dat data/filters/*
 
 #filterdir = $(datadir)/aten/filters
 #filter_DATA = data/filters/*
diff --git a/configure.ac b/configure.ac
index e59c0b629..f0c54aa17 100644
--- a/configure.ac
+++ b/configure.ac
@@ -37,9 +37,27 @@ else
   AC_CHECK_HEADERS([GLUT/glut.h], ,[AC_MSG_ERROR([Could not find GLUT header. Is GLUT installed?])])
 fi
 
+#
+# Additional Configuration Options
+#
+
+# MEMDEBUG
+AC_ARG_WITH([memdebug],[AC_HELP_STRING([--with-memdebug],
+    [Enable manual constructor / destructor counts.])], ,
+    [memdebug=])
+if test "x$with_memdebug" != "x"; then
+  AC_DEFINE([MEMDEBUG], [], [Enable manual constructor / destructor counts.])
+fi
+
+# SPEEDTEST
+AC_ARG_WITH([speedtest],[AC_HELP_STRING([--with-speedtest],
+    [Enable rendering speedtest (warning - makes compiled code otherwise unusable).])], ,
+    [speedtest=])
+if test "x$with_speedtest" != "x"; then
+  AC_DEFINE([SPEEDTEST], [], [Enable rendering speedtest (warning - makes compiled code otherwise unusable).])
+fi
 
-# Checks for GL, GLU, and GLUT headers
-# Provide --with options to specify the include locations
+# GL-INCLUDEDIR
 GL_CFLAGS=""
 AC_ARG_WITH([gl-includedir],[AC_HELP_STRING([--with-gl-includedir=DIR],
     [Set location of OpenGL and GLUT headers to DIR [default=auto]])], ,
@@ -48,8 +66,7 @@ if test "x$with_gl_includedir" != "xauto"; then
   GL_CFLAGS="-I$with_gl_includedir"
 fi
 
-
-# Allow Qt bin directory to be specified (to avoid version conflicts for moc, rcc, and uic)
+# QTDIR
 QTDIR=""
 AC_ARG_WITH([qtdir],[AC_HELP_STRING([--with-qtdir=<dir>],
     [Specify location of Qt4 developer tools (moc, uic, and rcc) [default=""]])], ,
@@ -58,22 +75,23 @@ if test "x$with_qtdir" != "x"; then
   QTDIR="$with_qtdir/"
 fi
 
-
-# Add in Apple Qt configuration arguments
+# QT-FRAMEWORK  (Mac only)
 AC_ARG_WITH([qt],[AC_HELP_STRING([--with-qt=framework|fink|<none>],
     [Determines which installation of Qt4 to use on OS X (should not be set for Linux)[default=<none>]])], ,
     [with_qt=])
+
+# GLUT (Mac only)
 AC_ARG_WITH([glut],[AC_HELP_STRING([--with-glut=framework|<none>],
     [Determines which installation of GLUT to use on OS X (should not be set for Linux)[default=<none>]])], ,
     [with_glut=])
 
 
-# Pre-initialise pkg-config since we don't know where the first PKG_CHECK_MODULES will occur
+# Pre-initialise pkg-config 
 PKG_PROG_PKG_CONFIG
 
 
-# Set up compilation for qt GUI
-AC_DEFINE([WITH_QTGUI], [], [Compile with the Qt4 GUI interface])
+# Set up compilation for Qt GUI
+#AC_DEFINE([WITH_QTGUI], [], [Compile with the Qt4 GUI interface])
 AC_DEFINE([HAS_GUI], [], [Whether a GUI has been specified])
 if test "$with_qt" = "framework"; then
   QTGUI_LIBS="-framework QtGui -framework QtOpenGL -framework QtCore"
@@ -102,6 +120,7 @@ else
 fi
 
 
+# Perform Makefile substitutions
 AC_SUBST(GUI_LDLIBS)
 AC_SUBST(GUI_CFLAGS)
 AC_SUBST(QTDIR)
@@ -113,12 +132,14 @@ AC_C_CONST
 AC_C_INLINE
 AC_STRUCT_TM
 
+
 # Checks for library functions.
 AC_FUNC_SELECT_ARGTYPES
 AC_FUNC_VPRINTF
 AC_CHECK_FUNCS([floor pow select sqrt strchr strrchr strstr])
 
-# Define AC_OUTPUT 
+
+# Define Makefiles in AC_OUTPUT 
 AC_OUTPUT(Makefile
 src/Makefile
 src/base/Makefile
diff --git a/src/base/debug.cpp b/src/base/debug.cpp
index 38f499ffa..9f91d986b 100644
--- a/src/base/debug.cpp
+++ b/src/base/debug.cpp
@@ -147,8 +147,8 @@ void print_memdebuginfo()
 */
 
 #ifdef SPEEDTEST
-int speedtest_numrenders, speedtest_totalrenders;
-clock_t speedtest_start, speedtest_finish;
+	int speedtest_numrenders = 0, speedtest_totalrenders = 100;
+	clock_t speedtest_start, speedtest_finish;
 #endif
 
 /*
@@ -159,14 +159,11 @@ clock_t speedtest_start, speedtest_finish;
 void prepare_debug()
 {
 	#ifdef MEMDEBUG
-	for (int i=0; i<MD_NITEMS; i++) memdbg.create[i] = 0;
-	for (int i=0; i<MD_NITEMS; i++) memdbg.destroy[i] = 0;
+		for (int i=0; i<MD_NITEMS; i++) memdbg.create[i] = 0;
+		for (int i=0; i<MD_NITEMS; i++) memdbg.destroy[i] = 0;
 	#endif
 	#ifdef SPEEDTEST
-	// Turn on idle events with a period of every second (for printout)
-	master.use_timer = TRUE;
-	master.set_timer_period(1);
-	speedtest_start = clock();
+		speedtest_start = clock();
 	#endif
 }
 
@@ -174,12 +171,12 @@ void prepare_debug()
 void print_debuginfo()
 {
 	#ifdef MEMDEBUG
-	print_memdebuginfo();
+		print_memdebuginfo();
 	#endif
 	#ifdef SPEEDTEST
-	speedtest_finish = clock();
-	double nsec = double(speedtest_finish-speedtest_start) / CLOCKS_PER_SEC;
-	printf("SPEEDTEST : Performed %i renders over %8.2f seconds (%8.2f/sec).\n",speedtest_totalrenders,nsec,speedtest_totalrenders/nsec);
+		speedtest_finish = clock();
+		double nsec = double(speedtest_finish-speedtest_start) / CLOCKS_PER_SEC;
+		printf("SPEEDTEST : Performed %i renders over %8.2f seconds (%8.2f/sec).\n",speedtest_totalrenders,nsec,speedtest_totalrenders/nsec);
 	#endif
 }
 
diff --git a/src/base/debug.h b/src/base/debug.h
index 749b23104..11159b451 100644
--- a/src/base/debug.h
+++ b/src/base/debug.h
@@ -87,9 +87,9 @@ extern memdbg_data memdbg;
 */
 
 #ifdef SPEEDTEST
-#include <time.h>
-extern int speedtest_numrenders, speedtest_totalrenders;
-extern clock_t speedtest_start, speedtest_finish;
+	#include <time.h>
+	extern int speedtest_numrenders, speedtest_totalrenders;
+	extern clock_t speedtest_start, speedtest_finish;
 #endif
 
 #endif
diff --git a/src/base/prefs.cpp b/src/base/prefs.cpp
index b88d99084..6672a0df0 100644
--- a/src/base/prefs.cpp
+++ b/src/base/prefs.cpp
@@ -281,8 +281,9 @@ void prefs_data::load(const char *filename)
 		if (!prefcmds.cache_command()) break;
 	}
 	// Check the flowstack - it should contain just the BC_ROOTNODE branch
-	if (prefcmds.get_branchstack_size() != 0)
+	if (prefcmds.get_branchstack_size() != 1)
 	{
+		printf("%i unterminated blocks in prefs file.\n",prefcmds.get_branchstack_size());
 		dbg_end(DM_CALLS,"prefs::load");
 		return;
 	}
diff --git a/src/base/sysfunc.cpp b/src/base/sysfunc.cpp
index e20552087..5b2feff11 100644
--- a/src/base/sysfunc.cpp
+++ b/src/base/sysfunc.cpp
@@ -325,8 +325,11 @@ const char *evaluate(const char *s, variable_list *vars)
 		}
 	}
 	// Look for non-blank argument and set it as result
-	for (n=0; n<parser.get_nargs(); n++)
-		if (!parser.is_blank(n)) return parser.argc(n);
+	for (n=0; n<parser.get_nargs(); n++) if (!parser.is_blank(n)) break;
+	if (n < parser.get_nargs()) return parser.argc(n);
+	// Failed to find a return value!
+	printf("evaluate - failed to find return argument.\n");
+	return ".0";
 }
 
 // Strip trailing whitespace from string
diff --git a/src/classes/dnchar.cpp b/src/classes/dnchar.cpp
index 03d93e2ad..903de92fa 100644
--- a/src/classes/dnchar.cpp
+++ b/src/classes/dnchar.cpp
@@ -34,7 +34,7 @@ dnchar::dnchar()
 	size = 0;
 	endpos = -1;
 	#ifdef MEMDEBUG
-		memdbg.create[MD_DCHAR] ++;
+		memdbg.create[MD_DNCHAR] ++;
 	#endif
 }
 
@@ -43,7 +43,7 @@ dnchar::~dnchar()
 {
 	if (data != NULL) delete[] data;
 	#ifdef MEMDEBUG
-		memdbg.destroy[MD_DCHAR] ++;
+		memdbg.destroy[MD_DNCHAR] ++;
 	#endif
 }
 
diff --git a/src/classes/grid.cpp b/src/classes/grid.cpp
index d02a05500..01d74f13c 100644
--- a/src/classes/grid.cpp
+++ b/src/classes/grid.cpp
@@ -40,7 +40,7 @@ grid::grid()
 	cutoff = 0.0;
 	log = -1;
 	style = SS_GRID;
-	displaylist = -1;
+	displaylist = 0;
 	colour[0] = INT_MAX;
 	colour[1] = 0;
 	colour[2] = 0;
diff --git a/src/classes/pattern.cpp b/src/classes/pattern.cpp
index 29e90c104..5a4beca87 100644
--- a/src/classes/pattern.cpp
+++ b/src/classes/pattern.cpp
@@ -93,7 +93,7 @@ patatom::~patatom()
 patbound::~patbound()
 {
 	#ifdef MEMDEBUG
-		memdbg.destroy[MD_PATTERN_BOND] ++;
+		memdbg.destroy[MD_PATTERN_BOUND] ++;
 	#endif
 }
 
diff --git a/src/classes/spacegroup.cpp b/src/classes/spacegroup.cpp
index 76642f9cb..63f738320 100644
--- a/src/classes/spacegroup.cpp
+++ b/src/classes/spacegroup.cpp
@@ -112,7 +112,7 @@ void symmop::set(const char *xyzstr)
 					rotation.set(n,v.x,v.y,v.z);
 					break;
 				default:
-					printf("Unrecognised character '%c' found in symmop spec.\n",c);
+					printf("Unrecognised character '%c' found in symmop spec.\n",*c);
 					break;
 			}
 		}
diff --git a/src/classes/variables.h b/src/classes/variables.h
index f3dfe5955..5fa1d6b88 100644
--- a/src/classes/variables.h
+++ b/src/classes/variables.h
@@ -107,7 +107,7 @@ class variable
 	// Get value of variable as double
 	double get_as_double();
 	// Get value of variable as float
-	float get_as_float() { float(get_as_double()); }
+	float get_as_float() { return float(get_as_double()); }
 	// Get value of variable as a boolean
 	bool get_as_bool();
 	// Get value of variable as pointer
diff --git a/src/command/commandlist.cpp b/src/command/commandlist.cpp
index 943c58b0d..128ca3b39 100644
--- a/src/command/commandlist.cpp
+++ b/src/command/commandlist.cpp
@@ -261,7 +261,7 @@ bool command::add_variables(const char *cmd, const char *v, variable_list &vars)
 	// Are there arguments in the parser that we shouldn't have been given.
 	if ((parser.get_nargs() - 1) > strlen(v))
 	{
-		printf("Too many arguments (%i) given to command '%s' (which expects %i at most).\n", (parser.get_nargs()-1), cmd, strlen(v));
+		printf("Too many arguments (%i) given to command '%s' (which expects %li at most).\n", (parser.get_nargs()-1), cmd, strlen(v));
 		dbg_end(DM_CALLS,"command::add_variables");
 		return FALSE;
 	}
diff --git a/src/command/flow.cpp b/src/command/flow.cpp
index a8ab27223..9d489493b 100644
--- a/src/command/flow.cpp
+++ b/src/command/flow.cpp
@@ -49,6 +49,8 @@ int commanddata::function_CA_ELSEIF(command *&c, bundle &obj)
 
 int commanddata::function_CA_END(command *&c, bundle &obj)
 {
+	// This should never be called....
+	return CR_SUCCESS;
 }
 
 // Loop over atoms
diff --git a/src/gui/canvas.cpp b/src/gui/canvas.cpp
index cfe9d9dcd..917879644 100644
--- a/src/gui/canvas.cpp
+++ b/src/gui/canvas.cpp
@@ -144,9 +144,13 @@ void canvas::init_gl()
 	dbg_begin(DM_CALLS,"canvas::init_gl");
 	if (begin_gl())
 	{
-		// Create lists for globs
-		if (list[0] == 0) list[GLOB_STICKATOM] = glGenLists(GLOB_NITEMS);
-		for (int n=1; n<GLOB_NITEMS; n++) list[n] = list[GLOB_STICKATOM]+n;
+		// Create lists for globs if this is the first call to init_gl()
+		if (list[0] == 0)
+		{
+			list[GLOB_STICKATOM] = glGenLists(GLOB_NITEMS);
+			for (int n=1; n<GLOB_NITEMS; n++) list[n] = list[GLOB_STICKATOM]+n;
+		}
+
 		// Fill display lists
 		create_lists();
 
@@ -215,6 +219,7 @@ void canvas::init_gl()
 // Create display lists
 void canvas::create_lists()
 {
+	if (!is_valid()) return;
 	dbg_begin(DM_CALLS,"canvas::create_lists");
 	// Generate quadric objects for subsequent use
 	quadric1 = gluNewQuadric();			// Creates a quadric object for use.
diff --git a/src/gui/canvas.h b/src/gui/canvas.h
index bbd356108..7652389d8 100644
--- a/src/gui/canvas.h
+++ b/src/gui/canvas.h
@@ -48,8 +48,7 @@ enum user_action { UA_NONE,
 enum key_code { KC_OTHER, KC_ESCAPE, KC_SHIFT_L, KC_SHIFT_R, KC_CONTROL_L, KC_CONTROL_R, KC_ALT_L, KC_ALT_R, KC_LEFT, KC_RIGHT, KC_UP, KC_DOWN, KC_NITEMS };
 
 // GL Objects
-enum glob_list { GLOB_STICKATOM, GLOB_TUBEATOM, GLOB_SPHEREATOM, GLOB_UNITATOM, GLOB_WIRETUBEATOM, GLOB_WIRESPHEREATOM, GLOB_WIREUNITATOM, GLOB_CYLINDER, GLOB_WIRECYLINDER, GLOB_SELWIRECYLINDER, 
-	GLOB_GLOBE, GLOB_GUIDE, GLOB_CIRCLE, GLOB_CELLAXES, GLOB_SELTUBEATOM, GLOB_SELSPHEREATOM, GLOB_SELUNITATOM, GLOB_WIREUNITCUBE, GLOB_UNITCUBE, GLOB_MODEL, GLOB_NITEMS };
+enum glob_list { GLOB_STICKATOM, GLOB_TUBEATOM, GLOB_SPHEREATOM, GLOB_UNITATOM, GLOB_WIRETUBEATOM, GLOB_WIRESPHEREATOM, GLOB_WIREUNITATOM, GLOB_CYLINDER, GLOB_WIRECYLINDER, GLOB_SELWIRECYLINDER, GLOB_GLOBE, GLOB_GUIDE, GLOB_CIRCLE, GLOB_CELLAXES, GLOB_SELTUBEATOM, GLOB_SELSPHEREATOM, GLOB_SELUNITATOM, GLOB_WIREUNITCUBE, GLOB_UNITCUBE, GLOB_MODEL, GLOB_NITEMS };
 
 // Forward declarations
 class atom;
diff --git a/src/render/render.cpp b/src/render/render.cpp
index a583efd45..5446bae34 100644
--- a/src/render/render.cpp
+++ b/src/render/render.cpp
@@ -121,7 +121,7 @@ void canvas::render_scene(model *source)
 
 	// Set the initial state of lighting in the model
 	prefs.render_style == DS_STICK ? glDisable(GL_LIGHTING) : glEnable(GL_LIGHTING);
-
+printf("Rendering\n");
 	// Draw the main model parts
 	// If render_point matches the model's total change point (from get_point()) then just re-render the stored display list. If not, create the display list.
 	glPushMatrix();
@@ -129,7 +129,7 @@ void canvas::render_scene(model *source)
 	  else
 	  {
 		msg(DM_VERBOSE,"Recreating display list for model '%s'...", displaymodel->get_name());
-		glDeleteLists(list[GLOB_MODEL],1);
+		//glDeleteLists(list[GLOB_MODEL],1);
 		glNewList(list[GLOB_MODEL],GL_COMPILE_AND_EXECUTE);
 		  // Draw the model cell (this also translates our drawing position to the -half cell point.
 		  render_model_cell();
diff --git a/src/render/surface.cpp b/src/render/surface.cpp
index f2be96834..68d24425a 100644
--- a/src/render/surface.cpp
+++ b/src/render/surface.cpp
@@ -447,7 +447,7 @@ void canvas::render_surfaces()
 
 		if (g->should_rerender())
 		{
-			if (list != -1) glDeleteLists(list,1);
+			//if (list != 0) glDeleteLists(list,1);
 			glNewList(list,GL_COMPILE);
 			  switch (g->get_style())
 			  {