Blender Crashes when moving keyframes

Support Animation and Rigging
1

Blender crashes whenever i move, scale, or position keyframes. Please excuse the awful animation but it’s the best i can do when it keeps crashing. I’m using blender 2.76b. I would be using blender 2.77, but for some reason it lags like hell on my computer. Can anyone else tell me if this happens to them when they try it? Also, ctrl Z triggers a crash too sometimes. This has never happened to me before, and it’s really infuriating. It’s impossible to work like this. Also, any time I save, it saves the blend1 as a blend@. So, it’s also giving me a bunch of errors for that. hopefully any coders here would know a fix for this? Or just a fix in general? Or, if you know how to make 2.77 lag less when moving the rig, that would be great too.
Download: https://mega.nz/#!wJdGyK6A!sGCmDPGqktZfMtcCilBW3qMBE_-0_ApEVdEcWKvMpNg

update: I downgraded to blender 2.74, and it works fine now.

2

Try changing the 3d viewport shading from Material to Textured or Solid view

Also, any time I save, it saves the blend1 as a blend@
Where are you trying to save ? Try saving to another location like your desktop

3

same issue.

4

same issue

5

Try reloading the problem file.