central locking problems

I have a 2000 TD5,a while ago the central locking fob stopped working on the boot door. It wouldn't lock or unlock, had to lean over & open in from inside.so the hubby took the door to bits, didn't know wot he was looking for & put it back together, but after that now both the drivers side doors won't work either now!! I have to lock the car with the button on the dash, lean over & lock the boot & driver side rear door from inside, then lock the drivers doke with the key!! When I unlock it the 2 passenger side doors open with the fob, but then I have to unlock drivers door with the key!! I've changed the fob battery & the alarm still works, do does anyone have any clue wot could be up please??!!! Oh & when you pull the handle on passenger rear door from inside, you have to pull it twice for it to open too!! Cheers!