If one wants to read the release notes, they are here.
A bug with 2.100 - when the 2100 rebooted with the new firmware, it was responding to two IP addresses, the one I had configured for LAN1, and the one that was there for LAN2, even though I have only one LAN connection. Trouble was I had another device at that same LAN2 IP. I changed LAN2 to not conflict and that resolved the problem, but it should not have been responding to that IP at all.
After installing new firmware I got one huge problem. Reset does not work. After rebboting everything was functional, but i was not able to get into administrastion. After reseting, box was not found by Install wizard, i was able to ping 192.168.1.100, but neither wizard nor browser was able to communicate with 2100. After power down, my "old" ip was still there, but no possibility to get into admin tool. Peter