Really strange, I got exactly the same problem tonight.
Ran the car, took it around the block, parked it back on the drive for a wash, wouldnt start after.

Exactly the same issue.... the coil lead will arc when put to earth as soon the ignition is on, but wont spark when turning over

I thought it was the group A coil which had died. Havent messed with any CPS/Dizzy.... could someone post how they should be please??

Thanks
Huw