is this a bug?

I'm trying to make a "selection box thing" like in lemmings. I added a "Pick random" event to make sure only one unit is chosen if the "selection box thingy" overlaps two units at the same time. This crashes my game, but ONLY if the units have a behavior. If the units do not have a behavior it works perfectly. I'm not sure if this is a bug though or if it's just me doing something wrong.

Here's the cap: http://www.mediafire.com/?yznml0wdew1

EDIT: This cap is without behavior added, try adding a behavior to the sprite called "unit" (any behavior will do I think) and it should crash.

It works fine for me, I'm not getting any crashes.

It works fine for me, I'm not getting any crashes.

I forgot to add a behavior to the sprite

If you try adding a behavior to the sprite called "unit", does it still work fine?

Ooh, now I see it. Yeah, it crashed when having the mouse over two of them and clicking.

Fixed for next build!

Which should be out tonight! Yay!