It's a bad limitation that right now, to rotate an image on a mockup, you have to do it BEFORE dragging it onto a mockup. The rotate widget gets disabled as soon as you drag the layer onto the mockup, which is inexplicably useless. It'd be a lot more fluid and flexible if you can rotate the layer (like a logo, type, other design on a T-shirt) WHILE it's on top of the mockup for live iteration — please make this happen, for better mockups for everyone!