Originally Posted by rick130

Double check the pump timing, as if it is slightly retarded, it will make the engine feel sluggish.
It can be the difference between the locking pin sliding in easily and a tight fit in the hole and plate.
After one belt change the engine didn't have the 'zip' I thought it should have on the test drive. Checked the pump timing and the pin went in but it was 'tight', so loosened everything off and reset as above and it was immediately better.

Simon's suggestion re checking the lift pump is a good one too.

Also, as John said, the sulphur does nothing to the fuel, (it's a contaminant) and the ULSD that is sold in Australia from the name brand service stations have added lubricity additives by law to replace the aromatic compounds that go ta ta when removing the sulphur.
Does the CEM injector stuff have a lubrity additive ?
If not, use something like Redline's RL2 which uses an ashless lubricant, as well as detergents and a cetane booster.