[Halon]

This is why it's hard to diagnose anything over the internet, we don't know the details until you tell us. To me now it sounds like the Link comms and the "car shuttiing off" are two separate things. If you're car is reading AFR's in the 10's, that's going to have a negative effect on how it runs/idles. If it sputters and dies when you're coming to a stop, that's different than an ECU just shutting down and the car turning off. So really it sounds like you're in dire need of a tune, as well as ensure you are mechanically set such as no vacuum/boost leaks, base timing and idle controls (BISS) set correctly.

So then the 2nd problem is you can't tune if you can't communicate to the ECU. So that may be a separate issue. Try a friends laptop, try a friends ECU, etc to figure out where the fault lies. Or if you don't have the means to do that, just send the ECU in to the Link guys, have them check it over and if they say it's good, then you know it's something specific with your car (maybe the access port).