The first screen said multiple objects, The reason is because that cart is a group. 1 of the pieces is the cart model and the other piece is a displacement showing it containts gold. This doesnt give you that entity window. You can right click and pick manipulate and just rotate it by giving the degrees as a value for Z. This should prevent you from having to ungroup it.
No, don't worry I'm not using HL2 textures, those simply look ugly when used in TF2.
Oh and BTW the second screenshot isn't even my map.It's some screenshot I found on the internet to show what I had meant.
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