Crash when using and going next to a key lock system

I was making it on creative but it happens on survival too.

All it is, is a chest that you put a redstone torch in and it sends to a hopper that sends out a torch if it gets full. so I have from slot 1 to 5:
41x76:0, 1x76:0, 1x76:0, 1x76:0, 1x76:0
then it sends the torch that got put in, up to another hopper that then sends it into a dropper and another hopper sends a custom potion with jump boost 10 and
then 2 ticks get sent to the dropper and get put in a chest but when I activate it it works then crashes me. But when I delete my player file it works but then i go over to it and it crashes me again I will try to post pictures of it if I can... Also this is in my multiplayer world but, it also happens in my single player. I also tried it without TMI.