[Equipment] Cisco SPA3102 Dial plan setup

Hello, I've recently replaced replaced the Thomson TG784 with a SPA3102 as the Thompson would cut off FXO/PSTN calls with static. Does anybody know how to setup the dial plan on the SPA3012 such that when something, say *1* is dialed before a number, it would be dialed through PSTN? It was a lot easier to set it up on the Thompson via Telnet as it was a lot more cut and dry. The dial plan settings on the Cisco seem complicated. Tips to reduce echo would also be appreciated. P.S. Is it possible to join an existing call on the PSTN line? Thank you.