Divorced and helping ex get mortgage

I'm a newbie so if helpful repliers need questions answered please ask - I'm not shy!

I am a husband who left 18 months ago and am trying to find ways of helping my ex stay in the mortgaged house while allowing me to get another mortgage.

I read another thread in which there were discussions about what could be done if the two parties in a failed marraige were talking. As I am the party that would be the obstructive one if I were that way inclined I feel that as I am not then there are things I can do to make this situation easier.

I am interested to know what could be done to help my ex-wife stay in the former matrimonial home with our daughters while allowing me to get a mortgage to buy a new place (I have been living with my parents for 18 months). She doesn't work as our youngest is not yet at school.

It is not avoiding paying that I am interested in, merely in getting my name off the debt (and to be fair, off the investment - she'd get the best part (90%) of the house and all contents).

It would also be useful to know about avoiding getting the CSA involved (amongst other things) and in getting the house into my ex-wife's name while she is not working. If anyone has any advice about what has helped them - what does she want from me, what could I offer to do to help? We are sort-of amicable, talking on the doorstep, but she won't sit down and talk (yet!). Maybe she would if I could persuade her I really am trying to help).

What advice would people give an 'ex-' couple who could agree to work together to solve some financial issues?