> jumping around the SERIN2 statement has the same effect as > commenting it out.
> (It will not be executed)

Of course it won't be executed either way, but commenting out the SERIN2 line significantly reduces your compiled code size.

> and all available ports are blinking LEDs on and off nicely.
> (Even with the RF transmitters antenna bound around the 18F)
> (I can't produce much more RF noise on the 18F, can I)

Definitely rules that one out..;o]

> It is SERIN2 that is causing a problem on the 18F, not RF or any > other noise.

That's what I was curious about. It sounds like you've already isolated it to SERIN2.

> This is probably the time to start a new thread: "18F252
> SERIN2 problems"

Not a bad idea. I have an 18F252 Flash-Stick setup with an RF receiver, but it's coded in C. I'll switch to PBP using SERIN2 and see if I can force the same problem.