Situation:
DM900UHD, stock software
Fresh installed plugin on Kodi.
Only plugin configuration changed is the IP address of my Dreambox.
On any attempt to enter [TV] then [Channels] on Kodi, the message "PVR manager is starting up at 0%" is displayed, and there is no progress.
Solution:
With great help from the author of the plugin, these two settings were found to cause the trouble:
In Dreambox Menu -> Settings -> Network -> Web interface
Token-based security: Off
Simple anti-hijack measure: Off
Additional information: Should you disable the webinterface, and enable it at a later time, these settings will revert to "on" (causing trouble again)