Success! Or at least to some degree...

Downloading the 3.0.12 FT3 update from ProFantasy seems to have resolved the import issue. (Why they require you to download the 3.0.9 version AND the 3.0.12 patch eludes me, but I suppose there are logistical reasons.) My bad - always get the latest version of the software before complaining. <sheepish grin>

I'm not 100% certain, but the "file corruption" issue I noticed may have actually been some sort of file sharing/locking artifact - as I've been unable to replicate the Wilbur error message when the file isn't open in FT3. Hurray for user error!

@beardo1976 - hope this resolves your problem, if it's still an issue.