The error is not caused by your script. Your script is technically correct (except for the accidental undefined reloadBlaster call in your latest post). The only problem it has is that p.health = 4; is a poor choice because, a) it's not obvious why this is done and b) the health change will cause a status update packet to be sent, which means unnecessary efficiency loss that could be avoided (finding a way to do so is left as an exercise for the reader).

The crash is most likely caused by the level alone but finding the cause proves troublesome. From the access violation error window, please provide the value of ESI.