I think I found a new problem concerning naming of scripts when you assign them to an icon or keystroke. Whenever a script contains a "_" character (like "a_b.js") and you assign it to an icon (customize toolbar) or a keystroke (Preferences/keyboard), the assignments are forgotten the next time you start Vegas. This also happens if you export keyboard settings and re-import them.

This problem seems to be related to the former bug in 5.0a where upper- and lowercase assignments were sometimes forgotten. This seems to be fixed now (I can memorize names like "doIt.js" now), but at leastthe underscore can't be used. I'm not sure what characters are precisely allowed though.