OK so i tried it, still failed. Looks like it's stuck with this or i upgrade the NVR if i wanna run a Colorvu camera.
Which version did you try to load... I would try it again with the firmware .dav file on a USB stick plugged directly into the NVR and start the firmware update on the NVR console GUI since you can't trust the browser GUI right now. Then see if you get the specific error "Device firmware mismatch"... or if you are lucky it will load that way.
As far, as upgrading the NVR goes, if you got the budget, it's a good idea... I upgraded from DS7616NI-I2/16P to DS7616NI-M2/16P and I am quite happy as the "I" series was not handling my Colorvu cameras too well... there are newer NVRs too with even more fancy features just to complicate purchase decisions

To really open a can of worms... If I was going to start over and upgrade everything (NVR and cameras) at the same time, I would probably switch to the Empire Tech Dahua brand NVR/cameras popular on this site and follow the advice of the experts here... not "chasing" MP, using varifocal cameras, etc.... could be a big learning curve though.