For #1 are triggering a floodfill when just hitting a ceiling. It doesn't look like it is.
For #2 I've noticed the snapping doesn't seem right at times. The equations I used do what they were designed to do: find which square on a staggered grid to snap to.
I did a test to evaluate the equation.
https://dl.dropboxusercontent.com/u/542 ... p_hex.capx
The formula is about the same as in the bubble shooter capx I've made before. I also compared it to just picking the nearest grid sprite which would be perfect minus the need all the sprites. Anyway there are subtle differences in the gaps. My conclusion is a new formula needs to be found so that snapping isn't done to the nearest square but the nearest hexagon, which would mirror using picking nearest.
A internet search for "snap to hex grid" would probably be the next step.
After that the issue of snapping into walls or other jewels may still be there and require another solution.