The CPC's internal +5V supply should be disconnected when connecting the external power-supply, otherwise something terrible might happen (for example, when one supply tries to output a few more volts than the other, or so).
The giant cooling plate (and the LM323K voltage regulator) aren't meant to be mounted directly on the PCB, but rather stacked a few centimenters above of the PCB (can been seen on photos in some of the later adverts).
== Alternate Versions ==
There seem to have been one or two alternate versions:
* The photo in the magazine original article showed a different PCB with giant cooling plate, which won't fit on the DIY layoutGl1 and Gl2 differently arranged. That photo may have been a dummy/prototype. Later adverts are showing the "normal" Gl1/Gl2 arrangement.
* The magazine later released a correction on their letters page which recommended to replace the 5K6 and 10K resistors on the L200 voltage converter - it sounded perfectly reasonable - except that, the DIY project doesn't contain any of that components. The correction (if it wasn't total nonsense) implies that the magazine shipped different PCBs to some people via their mail-order service.