Hello MattN,
your question is a cross-post: http://comments.gmane.org/gmane.science.physics.ifeffit/3475. while is permitted is also considered polite to inform about the other post. Infact many of the information you give here are yet present in the other page. You got also the author's support. is an important bit of information. Just for correctness.

Anyway dont fool yourself with the event viewer inspection: is very rare in my expereince to find something useful in them, and they costs hours of psychoanalisys..

Better if you concentrate on some trace tool: ProcessExplorer can tell you all about the DLL Hell; it has CRTL-D CTRL-H hotkeys to switch from handle view to dll one.

You can create with process explorer also dump of processes for further analisys.

Have you tried to put the right dll in the current directory? Assuming you can be sure what the current directory is when the program try to load the dll... current directory is searched normally as first thing.

i think i've terminated th possible suggestions.

L*