It seems the SKSE-plugin called “Crash fixes” (link to Nexus) is doing something (memory related stuff?) that causes vorpX’s Direct VR rotation scan to fail every time. As soon as I disable the plugin or change UseOSAllocators from 1 to 0 in the plugins ini-file the scan works perfectly.
This plugin has made my modded Skyrim a lot more stable, I just wish I could get the smooth Direct VR head movement + game stability at the same time.
Direct VR (partially) relies on values it searches for being at specific locations in memory. If any mod/hack makes changes to that in any way, like the one you are using seems to do, Direct VR may fail.
The only viable solution in such a case is to not use the offending mod/hack.