Same. Does anyone have a MacOS alternative they would recommend?
Since then, the logisim project has discontinued, but it looks like there is a open source successor:
https://github.com/logisim-evolution/logisim-evolution
Have not tried it, but it looks promising, provided you don't want to do too complicated things (not sure if you could really model complex CPUs like a pentium with it). Also, it's pretty digital only, so I wouldn't expect Mac-Spice-like analog circuit simulation.