https://bugs.winehq.org/show_bug.cgi?id=40476
--- Comment #3 from Mokou mokouthrowaway@gmail.com --- (In reply to Dmitry Timoshkov from comment #2)
There is the source of the project at https://code.google.com/archive/p/interactive-text-hooker/source/default/ source but it seems that it doesn't include the vnrhost.dll sources.
That's the source for ITH. ITHVNR is a different application (but contains some code from ITH). The latest source code for ITHVNR (as of 2016-06-18) can be downloaded here: http://www.mediafire.com/download/o1jvv62hodbl291/ITHVNR-3.5640.1-Source.zip Sources for vnrhost.dll seem to be located in vnr/texthook/host.
After a quick look it seems like it actually tries to work around some Wine issues, perhaps no one has tested it in Wine recently. Changing the IthIsWine() function to always return FALSE doesn't make it run, so I think it is a Wine issue.