logic pro x will not allowing multipule windows

Start and load the EastWest project, click play on the master project. The other thing is if you have different orchestra libraries, create separate projects with let's say one project has horns from EastWets, then create another project with horns from SpitFire. Need to go back, mute that rendered audio and just start that slave Logic Project and press play on your master project, now you can make further modifications. With that slave project unloaded, now you just free'd up your CPU/Memory to continue with your song creation. Just unload that slave Logic project, bring that audio into your master and click play, it's as if the slave project was still loaded. Do your tweaks, automation, adding effects, etc. Each is a separate Logic Pro X project, go to your slave project, uncheck the sync button, now it's a master project. So while you're creating you song you monitor the CPU, if your getting close to the limit, notice how my setup is. Cellos here, Violias here, Horns here, etc. Nobody creates a song with everything in it at once, it's a build process.

Not sure what technology was like back 16 years ago, but I'm pretty sure things have progressed.

If you have the hardware to run everything you can do that. This is the downside of all distributed-load solutions, everything is considered live and has to be processed in realtime. It was doable, but incredibly fussy, and - most of all - the CPU hit was so insane it was just not worth it.

I don't know how you rigged that up, but we did pretty much exactly that like 16(?) years ago to a) get around the 4Gb RAM limit which back then prevented efficient use of the then new orchestral libraries like VSL and b) set up a master-slave system with the slave(s) always fully loaded with instruments, so virtually no load times when switching cues which contained just MIDI.

Logic pro x will not allowing multipule windows