Moving platform heights not preserved in saved games

If any moving floor (be it a moving platform or a lift) is stopped mid move by a stop linetype (linetypes 54 and 89) and a game saved, then reloaded, its max height changes to what it was when the game was saved, rather than what it originally was.

An example of where this can occur with game breaking results in the original maps is the moving platform in the yellow key room on Level 13: Downtown.