I much prefer the ES1 version for it's smoothness. Might be good to have an easier switch, but I'm ok with editing .es file too. There is sometimes a crash in MeshBuilder::renderModel() when returning to main menu from the game, or when completing a level. gdb doesn't give an usable backtrace. Easiest way to reproduce is to complete Lara's home level (crashed 2/3 tries, ES1 mode, just run to the very end, jump into the pool and get out of it and the level should end). There is also an issue of bats not falling to the ground after dying (might be OpenLara bug). Seems to be ok in the ES1 version.