I tried reducing the start point of the if then that controls the delay from 400 down to 200 delay. The program now runs for 1 min 55 but gets further into the program. In fact it gets part way thru the "flashall" section. The power to the pickit demo board, the three darlington drivers and the opto couplers which operate the power transistors on the 8 positive lines is derived from a "Picaxe board I had lying around which has a7805 voltage reg and is being supplied from a 12volt 700ma power unit.
The normal output voltage which is going to the PIC is 4.8 I have written a bit of code which swithches on all three ports (and hence all 128 leds) and the current taken is about 220 mA which drops the voltage to about 4.2

For what it's worth the darlington outputs and the transistor circuits which light the leds are driven fom a car battery charger with an output of about 13.5 volts. Go on tell me I've done something daft !!! (I'll believe you !!)