CarpetRegrid2's "fixed box" functionality apparently prevents adaptive mesh refinement from occurring. When the parameter CarpetRegrid2::num_centres is set to 1, refined levels near increased level_mask do not appear, but they do if num_centres is set to 0. I have included a modified version of the AMRToy thorn whose only purpose in these tests is to set the level_mask in an annulus shape with larger radius than that of the fixed box. I have also included three parameter files, one in which there is only fixed-box refinement, one in where there is only AMR, and one in which there is both. In the test where there is both, I only observe the fixed-boxes showing up. The resolution of these parameter files can be increased to get better-defined AMR, but this low resolution still demonstrates the problem.