>>>Geesh! What a PITA that would be!
>>
>>Yeah, but I just thought of a better idea for ER:
>>
>>Have a switch to compile it in whatever older version you want, then the runtimes would still work as they ought to. (and it could check if you've used any newer syntax automatically, too)
>>
>
>Or add the switch to your compiled executable or config.fpw so that you can specify which runtime to look for.

That may be the simplest to implement. Just means you'd need to be more vigilant on the syntax use on your own (like it is now).