So it looks like for some reason that Google Drive reports itself as being FAT32.
FAT32 has well-defined maximum limits, including 4GB for maximum file size and 32GB maximum partition size.
Opus recently added a check for the 4GB maximum file size, to prevent attempting to copy files to (e.g.) USB sticks that will eventually fail due to exceeding the limit. This is what you're running up against.
I'm not sure what the solution is really, it seems odd that Google Drive would report itself as FAT32 when it apparently isn't.
I guess we could also check the size of the drive and assume that if it's greater than 32GB it's not "really" FAT32, although that just seems like layering one kludge on top of another