Since you have been using BiaB for 30 years I'm going to assume you are using a PC, correct?
Have you tried using the method in the microchord window? Does it work?
Maybe you could upload the song to the free Dropbox and post the URL so we can take a look at it?
Also the more information we have about your system will help tremendously. Things like CPU speed, HD or SSD, ram, free space on the HD/SSD, etc would be very helpful because at this point it sounds like the problem is with your system; it might not be but without more info we all would still be working in the dark.
Also have you run a full anti-virus scan? Have you used Ccleaner or Anti-Malwarebytes?

The reason I ask is because copy and paste in 4/4 or 3/4 works perfectly on mine and Audio Tracks machines.

Could others please check it out? It would be interesting to see if anyone else is having this problem or not. Thanx.

When you are at the checkout line and they ask if you found everything say "Why, are you hiding stuff?"

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware