>2.
>No, you can’t change the structure, because the header will get “corrupted” for FP2.6.

Yes, you can change the structure, just do not add any field types that are unique to VFP (like currency).

>6.
>Of course you can make any structure-amendment you like, as long as it’s performed in FP2.6.


Not necessarily. Just avoid the "VFP only" type fields and there should be no problems. Though one oddity that seems to work (and I don't know why): You can add a new memo field in either FP2.6 or in VFP (the sizes are different, 10 for FP, 4 for VFP) but either way seems to work just fine!