LT Spice Project is taking too long
I am suspicious of V2,V3 and V7,V8 possibly being the wrong way around...
Generally one should spice small bits of doings, running a whole system seldom ends well because it just gets madly slow even if it converges at all.
I would loose most of the +-15V power stuff, one of each will be quite sufficient and will make the model much simpler.
I would also simplify the thing to answer whatever the question you want to ask, rather then trying to build an entire power supply.