Assign the game to a single CPU core with Taskmanager (keyword "affinity"). It doesn't like multi-threading (or which ever way it splits it's processing across CPUs) and bogs down.
EDIT: This might help to automate things in the shortcut:
http://www.eightforums.com/tutorials...e-windows.html
I have in my shortcut Target line:
cmd.exe /c start "Subcommand" /affinity 2 "C:\Games\Subcommand\Subcommand.exe"
CPU0 =1
CPU1 = 2 and so on.