Tvheadend

I am happily running tvheadend using an Anysee H7 device to receive DVB-T streams.
Since I want to get a subsciption (only receiving FTA channels now), i wanted to get oscam running. however adding CWC clients is possible using the GUI, but I cannot enable them. So I started checking other options and it seems that the checkbox is somehow botched or something. Adding channel tags is possible, but I cannot enable them. existing tags cannot be set to internal, nor can they be disabled.

i really think I am doing something wrong, so can someone tell me what?

kind regards Tony