I know what you mean, I've played on a mac for years and it
was kind of frustrating... when I got my new mac I made a disc partition and installed windows just to have all the EPs and be able to create stuff! (plus I think the graphics of the game are slightly nicer in the windows version)
Anyways, I think you could achieve something similar with Fat D's design kit at MTS2
here, and using Silentlucidity's OMSP (also at MTS2
here) to place items on the horizontal beams. Hope this helps!