FPS Lag and Rubber-banding in SP

I am having multiple issues with the latest build. Glad Giraffe v3
My computer isn't TOP-TIER, but it's not bottom either.

Issues:

1. enemies have a ping lag type feel, in singleplayer mode.... they teleport around and animations are choppy despite having 50-60 fps
2. trees have the same effect when being cut down
3. huge fps lag when trees hit the ground, possibly due to particle effects and dust
4. huge fps lag at the outpost and arc

Attempted Fixes:

1. Run in...

FPS Lag and Rubber-banding in SP