I have the same problem with temperature on CRS212-1G-10S-1S+IN (no connection problems yet, but I have it for short testing time). SFP modules are very close each other. When the switch has full number of them (10) and they are turned on, overheating occurs. The temperature is going to 70-80°C (highest is on ports 5-6, of course) which is dangerously high, I think. There is no air flow between them. I think this is hardware design problem, SFP ports should be in one row only.
Unfortunately, this is the only Mikrotik model with 10 SFP ports, so we have no choice
Mikrotik, please make 2nd revision with full length (one row) or with some cooling.
Other guys: There is a fan hole on the back side. Did somebody tried to open the box and install a fan there? Maybe the warranty will avoid - but better than burn SFP modules and have connection problems, isn't it? Is there an official fan as an accessory? Is there a connector inside?