As far as I can tell, the glowing light just modifies the suspension to make it more sporty.
The E/M/S buttons on the left are responsible for adjusting the engine's characteristics; this button does not accomplish that.
Is it possible that the vehicle has detected your preferred driving style and adjusted the suspension accordingly?
get the most accurate quote, call the dealership or car locksmith. I would estimate that programming would cost around £150, according on a quick internet search.
Might not work with your slk55.
From the perspective of the E55k, the slk55 resonator and cats appear completely different. Regrettably, the ones I possess do not meet your needs.