PS2 Magic 2 MOD Big Snags

[sah]

Blimet this MODCHIP game is a painful process. I've just finsished installing a Magic 2 Chip (with a little help) into my PS2 V7 PAL. After re-assembly i tried an original. No problems. After this I tried a DVD backup; it didn't work and gave a message something like "insert Playstation 2 cd"). I ejected the backup and went for another try and after that the tray would not close. I stripped the console down to see if there was any obvious errors and am confident that the solder job was good. I disconnected the chip (I bought the clip kit to go with it) and the tray closed fine. I re connected and tried again and found that with a little tweeking of the standby button I could get the tray to close and open. So now I plug it all into the telly and guess what (no picture). I don't suppose anyones got any ideas have they???
I'm thinking of returning the chip as faulty and getting a MODCHIP 3.5. Is this a good idea??