Warlock: I didn't have any problems with it for a long time. Then they updated it and it started blue screening my PC. A later update seems to have taken care of it though. It's a fun little game, I just wish it had a campaign mode. After playing several of the maps (which can take a good long time to do if you do the large worlds, steam says I have 60 hours into it) I just didn't come back to it. A campaign mode likely would've drawn me back, but I can't complain at 60 hours. I might have to pic up some DLC and get back to it.
edit: hmm looking on paradox forums it seems they released a new patch Nov 15th that's been causing problems again (I haven't played since before then). It seems they release a patch with new features every few months (which is nice as some of the features have been pretty sweet) but they introduce a slew of bugs, some causing crashes, that you have to wait for them to fix (which isn't so great, almost like they don't have a good quality control testing process).