This patch allows you to change a level's initial background position depending on the level number.
I made this in a couple of minutes, unable to find an existing patch to do that (although I could have sworn one existed). Credit really isn't necessary.
Update: Now uses $0E instead of $010B to get the level number. Not only does this remove the need to have uberASM or something similar applied, it also fixes a bug where secondary entrances would load incorrect values due to $010B not being set at that point.