refreshing the browser a few times with 115 seems to solve the "different browser" error.
I find that with a lower powered PC (which is mostly what I have for channels) results in choppy video when the cc4c docker is on the same little machine as these machines are underpowered for this purpose. Running the identical cc4c docker on an 8-core i7 I use as a workstation results in very smooth video back on my channels server - I think cc4c is recognized as having a way higher resource requirement than the other "projects" and CDVR itself.
I think you have to check your specs and reset expectations on what cc4c (indeed as clever as it is) is going to accomplish for you in the short term without a hardware upgrade in some form.