Hi, I seriously need some help, I have given up trying to learn assembler and now trying picbasic but...

I have a PICkit1 flash starter kit, and am using PBP. All I am trying to do is flash any of the eight LED's on. I have copied a program from the manual and tried to adapt it but it just isn't working. I have ran the sample program to test the chip, so I know it is not broken.

DEVICE = 12F675
XTAL = 4

TRISa = %11001111

loop: High porta.4
low porta.5
Pause 500
Low porta.4
high porta.5
Pause 500
Goto loop

I am obviously lame at this but if anyone can get me started I would be really appreciative.
Matt