This seems to have been a fairly stable and bug-free launch, but keep in mind it's the first major release with a custom game engine under production called Dagon, freely available and open here: Dagon on GitHub[github.com]
Thus, there still seems to be some erratic problems occurring under very specific conditions. The vast majority of them should be fixed by updating your video card drivers. Note that support for OpenGL is mandatory. If you're having problems, please try the following:
Download the latest drivers from the video card manufacturer itself (don't use Windows update)
If that fails, edit the config.lua file present in the Serena SteamApps folder and set log = true. Run the game once and look at the contents of dagon.log. Usually, the reports give you a clear idea of what's going on.
If the engine complains about effects not being supported, try adding this line to config.lua: framebuffer = false. You will miss a lot of the eye candy, but hopefully the game will run.
If the mouse cursor is behaving like it's possessed by evil spirits, try setting verticalSync = false.
For audio related problems, try audioDevice = 1 or 2.
If you're experiencing sounds or music being cut, try numOfAudioBuffers = 8.
If all that fails, by all means, post a report here and we'll look into it. We're already investigating some of the problems reported.
IMPORTANT! There's a major bug on Windows XP that breaks the ending of the game. This is also our top priority (XP will be fully supported by Dagon).