<< That sounds like quite a bit of work and some forethought required to make it work... >>
In order - no and yes

No - Not hardly work or time consuming at all - Very streamlined and straightforward.
Select the save as Performance Track
and open the opposite bit rate version of BIAB if that's your final version. Performance files can be saved and work with both bit versions of BIAB in either direction - 32 bit to 64 bit and 64 bit to 32 bit. The Performance Files convert the RealTrack to a regular audio file.

Yes - Forethought to decide what your end product is...

To avoid any confusion, saving a track as a Performance Track, every computer with BIAB installed regardless of year, CPU, Ram amount, or OS will have no issue or strain to your project. The version of Amplitude that ships with BIAB has been tested and intended to work with that BIAB version in my opinion.

It's just a consideration I offered that shouldn't require jbridge, a DAW or power PC.

It's not meant to be a permanent solution or replacement for having a 64 bit version of Amplitude. That's a legitimate request.

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.