can you have one subinterface acting as a multipoint, and do you just map multiple dlci's on this interface ? and also where would i point the static route on this router, to the ip of the other end or just the local interface ? also I always thought it did not matter what ip you mapped the other end, does it really have to be on the same subnet ?
Yes, you can have a sub-interface acting as a multipoint interface. When using multipoint interfaces, it is recommended that you point it to the IP at the other end, not the interface. For IP to work correctly, you need to have addresses in the same subnet at both ends.