In order to run the 1522 APs, you will need to use the mesh code. I know that it is a hassle, but it is not recommended to run both mesh and non-mesh aps on the same controller. You would need two separate controllers. The only controller that will not currently take the newer mesh code is the older 2000 series controllers. The mesh runs a lot nicer on the newer codes. The release notes for the mesh codes will be able to give you more in depth information.