Heres the code....
opt C64=START ; Insert BASIC header, and jump to start of the code
opt A65816 ; Set 65816 assembler mode
clc ; Set processor to 65816
xce ; Set 16bit processor mode
If I dont put it into 16bit mode, it appears to work fine, but execute the rep #$30, and it dies.... I'm not sure why... If I didnt know better, Id say there was an interrupt going off - I wonder if the NMI's are still on....