The GOG release of this game works fine under CXG 10.1.2 (GMA 950 MacBook, 10.6.8) with the 3.02 patch released here: http://members.iinet.net.au/~peterykwong/lomse.htm
This fan patch fixes important bugs, and was originally preinstalled with the GOG.com release, but was later taken out due to ownership issues.
It's also worth mentioning that I've noticed major slowdowns with the map zoomed all the way out.