Oops! Spoke too soon. Although the feed itself is compiling all the posts I’ve asked it to, it returns an error in iTunes and on the browser I’m using (Firfox 3 for Mac). Also, the following error when run through Feed Validator:
XML parsing error: <unknown>:268:72: not well-formed (invalid token)
It does work fine in Google Reader and NetNewsWire for Mac.
I still need help!
I didn’t know about the # of posts per feed under WP Admin > Settings > Reading > “Syndication feeds show the most recent XX posts” option. Boosting that number solved the problem! Thanks for your help.