I have managed to get it working on both the app and mydlink.com.
Much as I cant quite believe, once I started accessing mydlink.com and the home IP addresses using Internet Explorer, everything started working fine, including the video playback on the home IP addresses. Microsoft Edge and Chrome dont seem to work as well, if at all.
There was also a problem with my DNR-322L installation - the extra Microsoft C++ or VB installation at the end did not come on automatically for quite a few times until I reset the 322L and re-installed everything again. This could have been the problem for the DNR-322L itself.
Thanks!