Hello!
About sprite placement, to make it easier to understand, basically, wherever you click, the sprite stay right there just like the regular tileset painting. I have several video that demonstrates that that you can find on my Youtube channel.
About sprite collision, the plugin doesn't support that. It does support grid-based collision but not sprite collision. There's a reason why majority of games use circle and square collision instead of using the actual sprite, this is due to performance optimization.