I've just started using Crossover on my Mac and I'm very impressed. Here's my results so far:
Steam, Halflife2, Counter Strike Source, etc.
Absolutely brilliant. Installed easily and run well.
Hammer (the Halflife2 map editor).
Unuseable. It starts, but it doesn't render correctly.
Dawn of War, Dawn of War: Winter Assault.
I copied the CDs to a directory on my hard drive and installed from there to get around the CD swapping during install. Patched the game, then installed a nocd crack. I then had to install DirectX. Now the game runs perfectly.
Civ4 (PC version)
I copied the CDs to a directory on my hard drive and installed from there. Patched the game, then installed a nocd crack. I then had to install DirectX. The game crashes randomly a few minutes into play, but at least it starts. I was lucky enough to enter negotiations at one stage, but the enemy player appeared as a floating smile. The log says that Civ4 was attempting to call unsupported DirectX routines and couldn't render correctly.
Stronghold Crusader
I copied the CDs to a directory on my hard drive and installed from there. Patched the game, then installed a nocd crack. The game runs perfectly.
Chessmaster 10
I copied the CDs to a directory on my hard drive and installed from there. The game refuses to start, citing "Can't bind to root surface with no fullscreen context".
Rome Total War, Barbarian Invasion, Alexander
I copied the CDs to a directory on my hard drive and installed from there. Patched the game, then installed a nocd crack. I then had to install DirectX. The map screen won't scroll down or right (up and left works fine, but leaves you stranded in the middle of nowhere). It locks up when starting battles (launched either from the map or from the menu as a LAN game).
E-Sword
After installation the program threw a few errors at me and refused to perform some actions. After I downloaded and copied a dll (I don't recall which one) into the bottle it ran perfectly.
I suspect that the hammer editor problem is the same as the chessmaster 10 problem.
I realise that nocd cracks are a grey area but as I own the original CDs for each of these programs I don't consider it to be a problem.
I'll be registering the product very soon and I look forward to supporting and watching the progress of Crossover.