There is info (and a good write up) around for changing the timing belt, making an alignment tool, VCT sprocket-to-cam alignment during installation (this is important). May be in the Zetec maintanence forum.
If the VCT solenoid coil has low ohm continuity and the computer is giving it voltage, it has to be stuck or blocked from getting oil (or timing jumped). Somewhere I read that you can jump the VCT to the battery to activate it. You could see it move with a timing light. Better research that though.
Read up anyway. The idler and tensioner should be replaced with the belt. May even want to replace the water pump while in there,
