gulp refuse to cooperate

[spadino]

Hi! Just installed the framework on my testing skeleton, and I'm trying to compile some modification to sass source.
When I call gulp, it give me this error:

[15:49:14] Using gulpfile /media/sf_www/middleman/kube/kube/gulpfile.js
[15:49:14] Starting 'sass'...
[15:49:14] Starting 'combine'...
[15:49:14] Starting 'scripts'...
[15:49:14] Starting 'watch'...
[15:49:14] 'watch' errored after 609 μs
[15:49:14] TypeError: vfs.watch is not a function
    at Gulp.watch (/usr/lib/nodejs/gulp/index.js:35:16)
    at Gulp.<anonymous> (/media/sf_www/middleman/kube/kube/gulpfile.js:62:10)
    at module.exports (/usr/lib/nodejs/orchestrator/lib/runTask.js:34:7)
    at Gulp.Orchestrator._runTask (/usr/lib/nodejs/orchestrator/index.js:273:3)
    at Gulp.Orchestrator._runStep (/usr/lib/nodejs/orchestrator/index.js:214:10)
    at Gulp.Orchestrator.start (/usr/lib/nodejs/orchestrator/index.js:134:8)
    at /usr/lib/node_modules/gulp/bin/gulp.js:129:20
    at nextTickCallbackWith0Args (node.js:489:9)
    at process._tickCallback (node.js:418:13)
    at Function.Module.runMain (module.js:443:11)
/usr/lib/node_modules/strip-bom/index.js:4
                throw new TypeError('Expected a string, got ' + typeof x);
                ^

TypeError: Expected a string, got object
    at module.exports.x (/usr/lib/node_modules/strip-bom/index.js:4:9)
    at /usr/lib/nodejs/vinyl-fs/lib/src/getContents/bufferFile.js:13:23
    at /usr/lib/node_modules/graceful-fs/graceful-fs.js:78:16
    at FSReqWrap.readFileAfterClose [as oncomplete] (fs.js:380:3)

I'm using a recently installed development environment in Ubuntu 17.04 - tested also in Debian 8 and Ubuntu 16.04...
I have rails, nodejs, npm, gulp, bower and grunt correctly installed and working.

Any clue?

There's also an alternative solution to compile kube.min.css without gulp?

Thanks, and congratulations for the awesome framework Kube is!