Not “improved compatibility”. Each of these is a real game that did not work on Linux, the exact thing that turned out to be wrong with it, and what is now done about it automatically. Nothing here needs to be configured — the fix is applied when the game is launched.
The intro is a run of video logos, and under a compatibility layer the first one can sit there for a minute or more before the menu ever arrives. It is not frozen — but nobody waits that long, and nobody should have to. The intro sequence is now skipped, which removes both the wait and the thing that stalls in it.
The community patch this relies on installs itself under a filename Wine replaces with its own version, so it was never being loaded to begin with. The game’s own copy now wins, which is what happens on Windows.
The Classic REbirth patch is a graphics library that sits beside the game, and Wine was loading its own version instead — so the patch never ran at all. The game’s own copy is now loaded first, with Wine’s kept behind it as a fallback.
That fallback is the whole trick: the patch passes anything it does not implement itself through to the real library, and with nothing behind it the game crashes instantly instead.
GOG ships this with a 3dfx graphics driver from the nineties, and the same shadowing problem applied: Wine substituted its own, and the game died before a window appeared. The driver GOG shipped is now used, which is the stack the release was built around.
Every file downloaded perfectly — but GOG’s installer normally performs three finishing steps afterwards, and nothing on Linux was doing them. Now applied at launch, repairing an install you already have, no reinstall.
Two faults at once: the configuration files GOG’s installer copies were never copied, and the game was being started from the wrong folder — so DOSBox looked for the game one level too high and quit. Both fixed.
One file was damaged on one of GOG’s servers — half of it, then the connection closed, every single time — and the download kept asking that same server for it. Now each piece is checked and a different server is used when one of them keeps failing.
Most things that go wrong under a compatibility layer are fixed by a general rule, and those rules are simply part of the app. What is left over is the awkward remainder: faults that belong to one specific game and to nothing else. Each one costs an evening to work out, and the reason for writing it down is so that nobody has to work it out twice.
The list is expected to grow. A game that has been added to it behaves, on your machine, the way it did on the machine where the fault was found — which is the only test that really counts.
Found one that does not work? Open an issue — this list is how it gets fixed.