[Renegade X - Open Beta 2 is now available!]

Is that folder really that important? System32 levels of important?

It's "lose most of your Start Menu" levels of important.

[Renegade X - Open Beta 2 is now available!]

Do you recall if you altered the default paths for any part of the original install?

Yes, to C:\Games\RenegadeX.

[Renegade X - Open Beta 2 is now available!]

So I'd hazard a guess that this happens if you're on a system with multiple accounts

I'm the only active user account on this machine, although as is the default for Win 7, it's not the Admin account. The uninstaller UAC-elevated when ran.

Where did you get this installer exactly? I'm starting to worry there may be a rogue version of the installer out there that's causing all these problems.

I got the open beta 1 installer from one of the mirrors on the download page from this site, although I'm afraid I can't remember which any more. Pretty sure I checked the SHA1 checksum, though, since one was provided, and all was well.

(As above, I haven't run the OB2 installer yet. The Start Menu damage was done by uninstalling OB1 manually in preparation, per the advice on the front-page news post. And, yes, I appreciate you're [also] asking Trev-MUN.)

[Renegade X - Open Beta 2 is now available!]

...this whole thing makes me concerned as to what Renegade X is doing with the registry when installing and uninstalling, as that part is glossed over by the installation log.

I'm hoping nothing. If it took a similarly broken approach, I'm not sure where to look for evidence of that.

While I'm at it, why exactly does Renegade X's installer require a restart?

What the beta 2 one? I haven't run it yet, because I'm honestly put off by the incompetence of the first.

[Renegade X - Open Beta 2 is now available!]

CREATE A SYSTEM RESTORE POINT BEFORE UNINSTALLING THE PREVIOUS VERSION

Dunno if it does this in every case, but the goddamn uninstaller is broken and can nuke AppData\Roaming\Microsoft\Windows\Start Menu\Programs, i.e. erase the entire per-user contents of your Start Menu. You can see it doing this if you hit "show details" during the uninstallation. If you have a system restore point (and at least Windows 7), you can at least browse to the Windows part of this path under your user profile (C:\Users\You\), select the Start Menu folder, and pick "Restore Previous Versions" from the context menu to get everything back.

Poor form to have not tested the uninstaller before releasing that first beta.