First - CONTACT PG SUPPORT !!!

Having said that, like MikeK I downloaded the everything Pak + 49 Pak using Firefox and Download Them all - installed and no issues.

HOWEVER, the error listed by OP above DOES NOT look like a incomplete or corrupted download issue, if that were the case I would expect the INSTALL not to have worked at all, the install would give errors and complain.

Looks like MAYBE privileges and/or MIDI, DXI, and audio app issues left "hanging" from PREVIOUS installed version or run (e.g., left in some pending condition)

Try a computer cold re-boot and reinstall then rerun and try

GOOD LUCK and AGAIN..... CALL SUPPORT
Larry


Win10Pro,i9,64GB,2TBSSD+20TBHDDs,1080TI,BIAB'24,Scarlett18i8,Montage7,Fusion 8HD,QS8,Integra7,XV5080,QSR,SC-8850,SPLAT,FL21&others,Komp.14,IK suite&others, just a guitar player-AXE FX III &FM9T, FishmanTP, MIDIGuitar2, GK2/3'sw/GI20