Thanks, but I don't think thats the issue. I've downloaded a few apps from the Market and they appear fine. It's just the old ereader app (not available in the Market, at least that I could find).
So I clicked on the "download the ereader for Android app" link (eReader_android_1.0.39.apk) but that's as far as I get. It doesn't appear in my Extras.
So do I need something else to actually install that file?