CTS 3000 endpoints will not register using SIP URI (even though they use sip for signalling and registering with CUCM)as Cisco tandberg does in VCS, and also its not provisioned to dial using sip uri's instead users can only use numbers to reach other endpoints. Im unsure if DMVPN can be used between sites since this is recommended for telepresence over broadband solution.
The below link show design for telepresence over broadband.
These are the paths to get to each CCX logs through CLI. They may be helpful if you are having issues accessing RTMT or downloading logs through it.
If you want to download them you have to prefix "file get " and you can add one of the options (re...