I've just tried cutting and pasting the code into a new page and renamed it - complied and loaded and got the same results when using C1 and C2 as the PWM pins. If I comment out the include "Multi_SPWM.pbp" the program runs fine, but I obviously have no outputs from the two pins.

So maybe you're right Henrik, in that there is some clash with the timing / or i2c bus ???