Upgraded a DS-2DE4220IW-D from 5.4.8 to 5.5.5 and had one issue.
It changed the web authentication realm from "DS-2DE4220IW-D" to "IP Camera(66041)" which meant that PTZ did not work in ZoneMinder until I changed the configuration.
I purchased a DS-2DE4220IW-D from an official UK distributor and it came pre-installed with V5.4.3 build 160810.
Unfortunately it shuts down all services every couple of days and the only open port on it is ssh.
Ssh'ing in and running dmesg reveals:
[237806.067154] [ pid ] uid tgid total_vm...