My menu looks like a folder

I would like to ask why, when I create a menu, it looks like a folder

By default new menus have the icon like the folder. You can change this icon: right-click menu button Appearance->Change Icon

and the shortcuts that I have put in there seem to refuse to show themselves (they did the first few minutes)?

Menu don't show shortcuts? How do you create them?

Also, more generally, can I put separators with text, and buttons, in columns directly on a toolbar, or do I have to put one or more menus on the toolbar to accomplish that?

Currently TLB don't support adding titles (separator with text) on toolbar dirrectly. You can add the separator, then right-click it and select "Change Title". Also to show the text on separator you must set "Show text" (View->Show Text).