Renault laguna electric window fault.

Hi, my electric window drivers side made a crunching sound. I flicked the switch several times trying to lose the cable and then nothing came from the motor. After opening the door panel the regulator was obviously tangled. Renault quoted 137 pounds foir a new regulator and said if it was the motor this would be 270 as well. Anyway i sourced another brand new reulator for 18 pounds delivered!! bit of a difference there! i fitted it myself but when it came to testing the motor still didnt work. I checked the 3 fuses in the internal fuse box and found there is another 20a fuse what they dont tell you about which controls the back windows. I checked these and still the motor didnt work. I then changed over 3 different motors to the regulator and still it doesnt work. I spoke to reanult and they said it wouldnt be the switch in the door. I tested this switch with a multimeter too and this gave a charge when the switch is pressed. Im thinking is it the wiring loom? is it possible the motors ive tried are duff or is there another fuse somewhere which controls the drivers side electric window. All other electrics work such as the electric mirrors etc. Any ideas????