Thanks for the replies guys! I've now found out that the mentioned temperatures are CPU temperatures, not enclosure temperatures. Today I've checked with one of those IR guns, and found out the switch and cloud key run at about 37°C, the USG at about 41°C and the AP's at about 44°C. Still pretty hot, but they function fine. I guess I'll just trust the tech and leave it as it is.

So far everything's ok.

Just got one problem though. I can't seem to access my Loxone home automation from outside the LAN anymore. With the old router I had set "port forwarding" up like below, and that has always worked fine. (first image)

With Unifi, I set it up like in the second image, but it doesn't work. It looks the same to me? Anybody got any ideas?

edit : those screenshots look pretty small, but I can't seem to make them bigger. I hope you can read them (you can if you zoom in on your screen).