
I used to play Quake 3 back in the day, and discovered Quake Live earlier this month. I was never really that serious about playing online when I was playing the original game (slow, crappy connection), and so I've been working on strafejumping and suchlike for a while using QL's tutorials (hall 3 is utterly effortless now EXCEPT for b2r which is freaking impossible

Decided I wanted to download DeFRaG and maybe play excessive, so I ended up cheekily installing Quake 3 onto my mac from the PC CD: if you create the framework and directories by downloading and installing patch 1.32 for mac first, then manually move pak03.pk3 from \baseq3 on the CD to \baseq3 under \Applications\Quake 3, you end up with a working copy of Quake 3 Arena on your mac. I'm pretty sure some people must have tried this on here.
After some initial random crashes, the game works absolutely fine, except ... ironically ... when I want to load a mod. I've unpacked Excessive Plus to the correct place, and the Mods screen recognises it, but whenever I attempt to load any mod, including the mission pack thing that comes with the point release, Quake 3 unexpectedly quits just after the screenfade (when you'd expect the selection screen to appear).
As far as I'm aware, pak0.pk3 should be identical regardless of what platform the game is on (I know that Quake 3 Gold was a hybrid CD), and it's pretty much self-contained, so despite the hotwired installation it should work fine. The only other problem I can think of is that the original CD had a minuscule scratch on it, but I doubt it would have copied (first to a new CD, then pak0.pk3 to the hard drive) if anything were corrupted.
Has anybody ever come across this problem, or can anybody see something I'm missing that might cause this to happen? I'd much prefer to get my legal, well-worn copy of Quake 3 working again than have to download a naughty copy of Q3G.

Thanks in advance.