Adding a curb under garage door? Do I need to adjust anything

it’s just an old lift master I assume cheap garage door opener

If I built a 2” concrete curb for the door to land on (because garage floor slopes a lot), do I need to adjust anything?

Currently, if I throw a 2x4 under the door will close on it and stop, but I don’t really know if I’m messing something up by doing that.