5. has lost its way!
I don't mean the categories, but the navigation on the page.
E.g. I'm in the "German" forum and then want to go to the "Forum Questions" forum, I can't find a list of forums on the page, for quick navigation, or I've overlooked something.
I have trouble switching categories when I'm in one.
7. Doesn't refer to new posts, but to posts where something has been forgotten. I think 5 times about just making a new one and naming the wrong one because links etc are lost etc.
GOOD:
4 & 5: It's not because of the forum software, it's because of the users

and you are all great.
6 Yes, is it because of the forum software? maybe, too old, nobody programs anything for it.
7 What do you mean? (Advertising)
8 It's not the software, is that a good feature? if there are posts that don't get replies?
9 I'll have to check that out.
10 That speaks for the community, but is independent of the forum software.
Gladly, it's important to address problems and try to understand what the needs are, because that's the only way we can grow together and become stronger.
We owe progress to the complainers. Satisfied people don't want change!
H.G. Wells