Wantok,
It's as USRanger says - the .res file should contain all the resources for the mission and no editing should be necessary. I don't know what to say, though. This feature works in house and I haven't had the opportunity to find out what's going on with the current beta release.
The wiki should, however, reflect reality (and I appreciate all your work on it, btw). Maybe that entry should be labeled a work-around so when this bug does get fixed the entry won't be immediately out of date.
- Sudz