IF S3D can read them without the SH5 adaption files?
Then they can be used.
Now. IF S3D can not read them without the adaption files?
You can NOT use them and there is a lot of work ahead!
There were a couple of us that did files for S3D so it can read SH5 files back in the early days of SH5.
If a smart programmer wants a project? A simple converter program could be done to convert from SH5 to SH3 and the other way around.
I'm just not interested in doing it although I know how.
How are you converting the 3D models?