I haven't done much on the project today, except to connect up the CPLD to the FT232 and succesfully load my VHDL 'programme' on to the CPLD.

This is always a nice message to see — it shows that I managed to solder the CPLD board at least partially correctly:

What wasn't so nice was the buzzing noise I got when I switched the PCW on. I can't think where I've gone wrong at the moment. All the pins connected to the PCW should be in a high-impedance state and shouldn't affect the PCW at all. I'm obviously wrong about this though!