It might be that the rail of the sliding table isn't parallel to the blade.
This can either be because the saw isn't set correctly into the CMS plate (which is what you should check first by measuring both edges of the blade to the long edge of the plate), if that isn't the issue then the rail itself could be off.
Mine had initially some play (at the left hand side where the rail ended) which stemmed from the plasting holder that sits in the v-grove having play, as I didn't install it correctly the first time (I didn't hold the rail down firmly enough, so the V didn't sat flush in the groove). I thought it was that it was a second-hand one, so I took it apart to look for worn pieces - but after reassembly it was OK, I couldn't move it anymore (toward and from the CMS, which before I had possible play of 1mm or so).
I would try: loosen both screws of the rail a little so you can move it slightly, hold it down hard on the side where the end is connected to the CMS-GE, tighten that screw, hold it down on the middle, tighten that screw. Then check that the sled rail cant move latheral, if that's good attach the protractor to the sled and see that it moves parallel to the blade.
When using the protractor fence on the sled as the reference edge: square it to the blade prior cutting.