I do have Windows XP on my MacBook (Bidule dual
core support works better under XP than under OSX) but I would rather
like to run it under OSX in order to combine it with some other
specific software.
Yes, it's a common request on the Usine forum. But as Senso (the sole developer) says: either you get frequent updates and new features (and updates are very frequent) to the Windows version or you wait a year or two to get a Mac version ...
Ian