There is already a huge thread on the forum about this.
IMHO nothing to worry about with the software side of things. Take the newer anti tune ecus, how is an mot tester going to read the map from the car?? how can they tell its mapped?
The only thing already in place which they could use is the eobd rediness pass/fail check for emission control. But a good map wont make a check fail to happen. Stage2 maps could end up with check fails, but this could be coded out in map with a little extra effort.