My 08 is catless with a 02 fix, runs fine on the TP stage 2. As they said, get that code fixed and you should be fine. You'll love the power bump from the new map.
I know the feeling, when I went stage 2 I found out I had a boost leak in the actuator vac hose. Got that fixed only to have the coupler on my tmic leak because of the retarded rubber boots they put on the hose from the factory, took it off, no more leak. A couple weeks later thought I blew my turbo, high pitch squeeling under boost. After replacing the turbo it did the same thing. Did a boost leak test and found out it was the other side of the tmic to throttle body coupler. The rubber boot on the throttle body end blew out causing the high pitch squeal when the air passed through it. Took that boot off and clamped down the hose, finally running issue free.
Turbo cars can be a PITA, but they're worth it.