Re: 1.0 RC – How to force all post into 1 category?
Frooyo, to answer your question, you can remove that dropdown as you did, but first you need to add the forum name as hidden value to the form. You can look at the source of a rendered page, find the select, grab the form field name and value, and just code that into the form as a hidden value. That way, when you submit the form, it looks the same to bbPress as if someone had actually selected one (of one) value for a forum name.
Mine looks like this (your forum ID might be different):
<input type="hidden" name="forum_id" value="1" />