I see another comment says you're using Chrome - I use Chrome, it should work in there. (I try for other browsers too, though!) What's the error message you're seeing?
Basically, the glitching I am having is where at a certain point of progress, the menu buttons either disappear, or overlap other buttons when in a sub-menu, thus preventing me from progressing properly.
Could you possibly send me a snapshot/some more details about that? I haven't been able to reproduce any button glitches, and if I can't find it, I can't fix it.
I see another comment says you're using Chrome - I use Chrome, it should work in there. (I try for other browsers too, though!) What's the error message you're seeing?