I'm trying to purchase one of your In-App items and it keeps giving me the error "An error has occurred, please try again". I know my internet connection is good and I can purchase other packs so.....

This is a rare case, but is caused by an update going live before the inapp pack has been approved by Apple.

This delay is usually brief, from a couple of hours to around 2 days. We'll try and keep users updated on these situations via the inapp news and our forums when they happen. Basically, just try again a bit later.