[garageband]

Hi. Welcome. There are very few folks on this forum running Macs and necessarily even fewer running Logic. Me: the former, not the latter (I use DP).

If I had this happen, what I'd try is the open the offending project, deinstantiate the offending plug-ins. I might even take them all off. Keep in mind you're doing the essentially difficult thing of opening one program's file in another. Not pleasant no matter what programs or platform involved. Also, trash the Audio Unit cache so Logic will rescan for available plug-ins. Actually, I'm not sure this is the way Logic does it. Consult the manual.