I can't execute gulp build, and therefore my theme renders poorly (no css, no fonts, etc.)

I've installed the required environment to work with nvQuickTheme, and everything seems to be in place. But when setting my dev DNN to use the theme, it won't work. Lookiong for the cause, I see that I dont have the /dist folder. So I try to build the theme, but when I execute (in Git Bash) gulp build a get the error "Task never defined: build". In fact, if I list tasks (gulp --tasks) I don't see the build task. Another thing I've noticed is that package task is now called zippackage. Maybe I didn't installed everything correctly?

Thank you for any help ;-)