The game is pretty buggy, especially cutscene animations. Patch 3 introduced the jumping bug. Textures load in for 10 seconds like you said even after the load screen.
Each patch seems to have helped lessen some of the bugs, but a lot still exist. Hopefully Patch 4 fixes some of them.
I've also played the game on 3 different computers and a poor gpu seems to lead to more performance issues than a computer with a good gpu but poor cpu. Keeping the graphics card up to date also tends to help lessen some texture glitches for the water and fire.
