I'll be out of town this weekend, sorry to say, but happy to help with last minute advice...

BTW, if you have a nice evening and want a beer and a great view, check out Letna beer garden. Riegrovy Sady isn't bad either, although the nice view (of the castle) is not visible from the beer garden itself...you'd have to buy a beer at a store and take it or ask for a beer to go (sebou) from the beer garden...they'll give you a plastic cup.