Years ago, I had a similar problem with my inbound DAHDI lines. I ended up sending each of the lines to a special context that added the line’s DID. If I remember correctly, there’s a way to do that from the GUI now. If you can’t find it (or figure it out) let me know and I’ll drag out those old contexts and send them to you.
As far as inbound Caller ID goes - that comes in as a special “text entry” right after the first ring. The AdTran shouldn’t be stripping that off - it would have made the inbound CID on your old PBX not work. I’m gonna guess that there’s a problem in your initial config that’s messing it up. I have no idea what it could be (I’ve never run into problems in CID from DAHDI) but it’s probably something simple.
There are lots of things in DAHDI that violate the rule of “least astonishment”, so just keep playing around with it. Look in the original dahdi config files - there’s one of them that has every DAHDI option and it’s settings and meanings. Also, check with your phone company and see if they can shed some light on why the CID information might be failing.