Yes, in theory you can combine all your existing material by copying it to another location where BIAB is installed. Make sure whatever copying software you use will overwrite only older dated files.
I do this every year.
HOWEVER in BIAB 2018 they substantially changed the folder organization. If you are trying to recover files from 2017 or earlier onto a drive with BIAB 2018 or later, it won’t work directly. I urge caution and suggest you call PG Music Support for guidance how to proceed. Be prepared to detail everything you have and exactly what you want to do.
While I and several other fellow users have the experience and skill to do this, we cannot take on the responsibility of guiding you here in case something goes wrong.
Yes!
The process is similar—nut not identical—for the Mac.
I save every install EXE file.
If you did not, log in to your BIAB account (different from your Forum account) and everything you registered is there.
Some versions only ship on external media. Audiophile ships on an HDD. Once received, I install everything into my Mac — Drums and Real Tracks are about 1.5TB so they go to a TB3 SSD*. I have to remember to reinstall all of my Extras packs both onto my computer and again onto the drive that I got from PGMusic. Same thing with Updates—both the Mac and HDD. Since I do everything twice, I find it faster to just run the individual installers than use the Install Manager though that is getting better.
*Is this really necessary? Not really as the overall speed and loading from the HDD is reasonably fast; my iMac Pro and Mac Studio are a
lot faster, no denying that. There are reasons I prefer to do it this way, however. First is that I dislike the noise from the HDD. It's easier and faster for Time Machine & Backblaze to back it all up. I like having everything up to date on the HDD in case I ever had to restore from it.