I spent quite a while (at least for me) on this last year.

I concluded that if it can't work across all PICs and all versions of PICBasic consistantly everytime, it shouldn't be used.

The only ways I address PIC pins is by aliasing the pin or by using the direct numeric (0-15).

The offset addressing method works for RAM and I've detailed this in the FAQ section, but I cannot reliably apply the same to Port Addressing. I have not redone my tests on V2.45 which had not been released at that time.