This page is a history of most Mac versions of Unreal Engine based games (mainly ones release by Epic).
Contents
Unreal
Ported by Westlake Interactive and published by Macsoft, UT was never really finished in terms of patches, which makes network games incompatible with the Windows version. It also has a nasty bug that occurs on some graphics cards (mainly ATi models) that causes lighting to function incorrectly, causing everything to appear very dark. This makes it very difficult to see where the hell you're going on the darker maps. Obviously, software rendering mode doesn't suffer from this problem and is probably the only solution if you're suffering from it.
Patches
The last patch made available for the Mac was 224b7. As the version number suggests, it was still in the beta stage when released. Since the latest (and last) Windows patch for Unreal was version 226f, which isn't compatible with the 224b Mac patch, as stated previously network play is broken between the two platforms. The patch used to be on Beyond Unreal's Essential Unreal Files page but it apparently no longer is. You can still get the patches (either the full b7 or the full b1 and the update b7) from Fileplanet but you need an account to download them:
Return to Na Pali
RTNP is the Digital Extremes 'mission pack' for Unreal. This was never released on the Mac, and unfortunately because it's not actually a 'drop-in' modification (it doesn't require the original Unreal to play it), it can't run at all on a Mac in the conventional sense. It is possible however, to use Unreal Tournament to run the pack instead, using a modification called RTNP2UT. The mod is obtainable via Fileplanet, a direct link to which is located on dinwitty's web site. If you go through the ordeal to download it you might also want to look at this thread on the BuF. Just FYI in case it wasn't obvious enough already; in order to play the mission pack, you actually have to own it. The mod only contains a few altered .u files to enable play, it doesn't provide you with the maps or any other material.
Editing: Maps & Mods
No UnrealED or UScript compiler was released for the Mac so mapping and modding isn't possible on the platform.
Unreal Tournament
Although ported to the Mac, like its predecessor it has had its fair share of problems on the platform (probably more so than the Windows version). After the initial release of UT for Windows, it was again decided to get some third party porters in to do the Mac version. The job of porting it was given to Westlake Interactive... Again. The Publisher would also be Macsoft yet again, although at a later stage Infograms took over support for the Mac version (seeing as Macsoft was a subsidiary of Infograms).
Patches
The last official patch that was made available (in sync with the Windows version of the game) was version 436, which should still be downloadable from BU's Essential UT Files page):
Patch 436 squished numerous bugs, and even brought in some new ones (as most patches often do). However, there is still an extremely annoying sound bug that usually occurs on most Mac systems running the classic OS (OS 9.x or below). It won't occur on OS X if you use the preview builds, but that's because the music is broken completely in them anyway.
The intensity of the bug seems to vary depending on the system you use. It also seems to vary how quickly it manifests itself. For instance one might be able to play the game perfectly for a short period of time without experiencing this problem, but it may become apparent after a few Map changes that music no longer plays, and sound effects don't seem to play at all, or if they do, the wrong sound plays and usually gets echoed to infinity. There is no known fix for this problem on Classic, despite what Westlake have said in the past about using different versions of the Sound Manager. Support for the game was dropped entirely a long time ago, so it won't get fixed officially now.
The game isn't playable on OS X natively without using a preview build Westlake released; the latest being Preview 3 and was far from complete - Westlake even said that because they were doing it in their own free time that it might never get finished... And low and behold, it didn't. There was talk of a Preview 4 some years ago but that never materialized... Shortly thereafter it seemed Westlake dropped support for the game completely. In any case Preview 2 can be found on Fileplanet, but Preview 3 appears to have disappeared (it does tend to float around certain torrent websites).
Expanding on the OS X side of things, Ryan Gordon is (or rather was) attempting to make a Mac 10 update as part of UTPG. That apparently got put on the back burner some time ago though, (the last mention of it on Icculus was back in 2005). UTPG itself hasn't been updated since 2004 either. Maybe one day a UTPG patch for OS X will be finished, so keep an eye on this page just in case hell freezes over.
Editing: Maps & Mods
It is not possible to make Maps or Mods if you have the Mac version of the game. That's because there is no UnrealEd for Mac, as nearly all Mac users who play UT are probably well aware of. There is also no UnrealScript compiler available, or indeed other less important tools that might have been useful such as a UMOD creation tool, even though Westlake had the kindness in their heart (/sarcasm) to create a tool to install UMOD files which comes with the 436 patch. There was a project called Seppuku that was supposedly trying to create a tool for use on the Mac that would support various other Unreal Engine based games as well. The project seemingly never got out of the idea stage though.
UT 2003 & 2004
Both were released for the Mac. Not by Westlake either (hurray!). Patching was kept up to date with the Windows version like UT except no "show stoppers" were seemingly introduced (or indeed went unfixed) as was the case with UT.
Patches
The latest patches for the two games are available from Macgamefiles:
Unreal Tournament 3
Currently the Mac version of UT3 remains unreleased, but supposedly work is continuing on it and it should see a release soon along with a Linux version. The exact reasons for why it has been delayed for such a long time have not been disclosed, though it is believed to be something to do with a lot of "red tape".
Editing: Maps & Mods
I'm not too familiar with the current situation behind UnrealEd on the Mac this time round though going on what was mentioned here it is a very good possibility it will finally see a release.
For UnrealScript editing there is an application for Mac OS X called Unreal Writer
Other Games
There have been numerous other non-Unreal games released on the Mac that use the Unreal Engine. Details of exactly what games have been released can be found on the Unreal Engine Versions page, although as for which got Mac releases, some of the more popular titles include Deus Ex, Rune, Undying and even the newer XIII, and even Postal 2. None have a Mac version of the map editor available... There's a surprise.