I like the concept and think if refined it has good potential.
Furegus covered the game's core issues very well so I see no reason to further dwell on that. A lot of the games issues can be fixed by improving the guards A.I. and with some more intricate level design.
Level design is a crucial part of game development and it's one of the things that causes a decent chunk of this game's issues. The levels are far too massive, there needs to be more turns, dead ends, and walls limiting the player's movement and giving the guards a chance to catch them.
As for bug reports I only found one major one. You need to limit the players ability to move the cursor out of the game window. if the user has multiple monitors it makes the game nearly unplayable as your cursor leaves the game window when you try to turn.
All this being said, finishing a jam is a major accomplishment in of itself so while the game may not have came out perfect you can definitely be proud that you at least put in the hard work to get it done!