Lag While Working on My Map

It's really hard to work on my map if I have to wait 4 seconds everytime I place a tileset, does anyone know how I could reduce lag while I'm working on my map?

EDIT: Doh nvm I found a post on how to reduce lag. Thanks anyways for anyone who read this.

Look at the reduce 95% of editor lag thread near the top. I don't know if it reduces lag with tilesets or whatever your problem is though...

go up to window and disable brush list