Anyway, I'm guessing from the screenshot that you're also on Windows 7, which means it most likely is an environmental issue in that it's the operating system itself.
*slaps forehead* All that information was clearly in my mind when I wrote that post, didn't you read it?

Yes, Win 7 64 bit Ultimate. Fairly fresh install, less than a week old.
So, if any version of Win 7 was gonna have what Chummer is trying to use, it would be this version.
Putting on my "programming cap," I'd say it almost isn't worth looking into if it is a Win 7 only issue. With Redmond threatening to EOL Win 7 any day now. Annny day now.... Any day now.

Strictly as a user though, I would like the support for PDF in Chummer.
As for
needing PDF support... That really isn't an issue. For starters, anyone I would send a PDF to, could just as easily open a html file. Not to mention there are many other way to get around that particular issue.
I would rank it solidly in the "quality of life" category, for me at least.