FridgeMagnets: Magnets get stuck into drag mode and crash the application when using virtual cursor and keyboard

Sometimes Fridgemagnets magnets get stuck into the drag mode, and crash the application.

Steps to reproduce:
1) Start fridgemagnets
2) Navigate the virtual mouse cursor on top of one of the draggable tiles, e.g. the "Colorless" tile.
3) Press select followed immediately with a directional key while still pressing on select, i.e. just like you would normally do when starting dragging the tile.
4) Instead of dragging the tile, rapidly release both keys -> If you did this correctly, the draggable tile disappears and is replaced with a circular cursor. Repeat if this doesn't happen.
5) Press any directional key without pressing select -> Usually the magnet is dragged along, which is incorrect, since select is not held down. Worse still, sometimes the application just crashes with KERN-EXEC 3.

Note that this crash seems to occur only when dragging one of the larger tiles. This fact along with the unpredictability of the crash suggests this is a timing related issue.