Well i could fix it for you but then you'll have to ship it to belgium.Since you have the equipment that would be a bit stupid.Let's try to fix trough this topic or email.So first check the 5V,starting from the dc adaptor input trough a diode (1N400x),then a cap into a 7805 regulator.If you have 5V at the output of the 7805 then the next thing to check is if you have a clock signal on pin 6 of the Z80 µcontroller.I need to check it out but i think it works on 2MHz.I have the pcb of MC-1 here and it seems it has a 4MHz crystal (buffered by a 74HC04 (hex inverter) pin 1 and 2) going to pin 3 of a 74LS74 (D flip flop),there it will be devided by 2 so you will have 2MHz on pin 5 of the 74LS74 then it goes to pin 3 of the 74HC04 and pin 4 goes to pin 6 of the Z80.Also make sure sure pin 26 (reset) is high (5V).
I hope this makes sence,if not let me know.BTW the 74hc04 is on the right side of the crystal,the LS74 on the left side.