Registax 32 bit FIT files- why don't they work in other programs?

Can anyone answer that question? I have tried opening the Registax 32 bit
FIT files in many other programs, but all I get is either total darkness or
a small bit of a picture that is unusable. The 16 bit TIFF files seem to
maintain compatability, but definitely not the 32 bit FIT. Anyone know why?
Apparently, I'm not alone as I understand and have read of others
experiencing the same results. This is a shame because the 32 bit files
would be so much better when used in the other programs.

Thanks for your thoughts,
Blaine