No worries, just don't want others temporary bricking their NVRs.
For under £100 direct from UK the 7108N-SN/P is a mini bargain. Having said that I'm never buying Hikvision ever again.
Just got a Dahua NVR1104-P for a friend (same as 7104 but Dahua), not installing it for a few weeks but will...
Don't mix and match Hik with other brands.
I'd keep e-mailing hik until they finally give in and allow you to reset the password rather than buy another Hikvision which you could end up in the same boat with.
Are you using a Dahua NVR?
KW12P - you're never going to get amazing nightvision from a higher MP model and you won't get 2-way audio from an outdoor model.
Sometimes you've got to try to do stuff in order to diagnose and fix things... you never know and it's not a huge effort to unplug some RJ45s from the back of an NVR.