Hi all, I can sense the geek aura around here!

Let me start by giving you a synopsis of what we want as a school:
Ability to have wireless IP phones
Ability to have IVR
Ability to rid ourselves of the Comdial FXII nightmare

With that said, here's my current situation:
Comdial FXII with Expansion cabinet
PRI to PSTN
PRI to Asterisk
100 Comdial digital phones
5 Asterisk IP phones

Done so far:
DID for each comdial extension on block 2 for the line group 2 (* to Comdial PRI)
Line group 2 accessible by pressing 6 (the same way you press 9 for PSTN access)

Issues:
How do I call through from asterisk to the PSTN? Is there a way to route directly from one PRI to the other? If so, I don't understand how to get around the DID's. The issue also exists the other way around: How do I call through from the PSTN to asterisk?

How do I transfer a call from Comdial to Asterisk? Every time I transfer to my asterisk phone, I can chat with that person until I hang up to complete the transfer, then comdial drops the call and puts the transfer on hold.

I know that most of you probably have no clue about asterisk, but I only use it as my example. All the issues are comdial-based.

Thanks for your time!