What do you mean by it has a working EGT gauge? An aftermarket gauge has nothing to do with the issue - You need to have that CEL cleared and if your sensor (not gauge) is still in the UP without a cat it needs to be removed. You can disable the CEL in the map (or your tuner) or you can do the resistor mod.
What is going on with the other CEL regarding the radiator fans?
You need a correct tune for the boost control system without the MBC. Do you have a DP? If not you can use a stage I map or the stock map, if so try a stage II map, or go get it retuned correctly. What kind of EBCS do you mean it has (do you mean the stock boost control solenoid)? If you have like a grimmspeed EBCS that takes a different map/tune.
These are all things that have to be taken care of ASAP - it may or may not completely fix your issue but we won't know until you get caught up.