I've been using it for production!

Just been using Spred for a small production (not sure when I can show anything...yet)

Main things:

X - to flip X ( I use this often for the left facing version of sprites)

F1 (prep currently hoverred over sprite for a swap), F1 again, swap with the new hovered over sprite.

Up/Down change layers (Toggle Tab to see layers used) a small 1 in a circle means you have placed on layer one) use Ctrl and arrow to offset it.

Placing a sprite in anything other than layer 0 will make it transparent based on the bottom-left-most pixel colour, so avoid plotting there or your sprite may disappear in areas or fully. (its a feature, not a bug).