The community member @Pedro was able to solve my cropping issues for WCIV. I had a similar issue with WC: Prophecy and spent many hours trawling threads, in an attempt to pin down the cause. Eventually, I was able to discover the solution myself and thought that one good turn deserves another. As such, here's the most likely solution for anybody having the same issue...
The FMV sequences being cropped are due to the combined configuration of 'nglide_config.exe' and 'OGLsetup.exe'.
The settings which worked for me were...
* Vulkun (video backend) and Fit to Screen for 'nglide_config'.
* 1920x1090 for 'OGLSetup'
If there are still issues, then selecting different resolutions and/or options will likely fix the issue, depending on your own monitor. Ultimately, it does appear to be an issue relating to the settings selected within those two specific configuration programs.
The FMV sequences being cropped are due to the combined configuration of 'nglide_config.exe' and 'OGLsetup.exe'.
The settings which worked for me were...
* Vulkun (video backend) and Fit to Screen for 'nglide_config'.
* 1920x1090 for 'OGLSetup'
If there are still issues, then selecting different resolutions and/or options will likely fix the issue, depending on your own monitor. Ultimately, it does appear to be an issue relating to the settings selected within those two specific configuration programs.