[quote name='Rollobobo']OK, I must be late to the party here, what's the download history glitch?!?[/QUOTE]
Your purchases through the app do appear in your history, but regular Marketplace doesn't recognize them and proposes you to buy them again instead of showing the usual "already purchased" line along with the option to re-download from scratch.
Vice versa, items already bought in the Marketplace aren't recognized within the Sales & Specials+ app, which lets you buy them again, so you have to be wary of your purchases before attempting to take advantage of the app's discounts.
My Ms. Splosion Man, bought as a discount with the S&S+ app, still shows up as a regular 800 MSP purchase in the Marketplace, so I'm scared too to delete and then try to re-download it again through "normal" means...