I am trying a different approach. The reason my file is so big is that I have a huge branch of my husband's grandmother's family (about 40,000 people) that we got from a distant relative (turning out to be a major mixed blessing). Anyway, I have a FTM 2011 file that doesn't have this branch of the family (about 600 people) that I am going to experiment with. I've exported it as FTM 2008/2009 and am currently importing it. Looks like it's done, so I'm off to experiment!
I guess I have to figure out what to do with the 40,000 relatives we have courtesy of the distant relative. We got the data in a GEDCOM file originally. Perhaps I'll try uploading that separately....
Thanks