I recently came upon an issue where attempting to write a memory via a backdoor yields a warning similar to the following:
"reporter [RegModel] Memory 'tst_reg_blk.test_mem' is not contained within map 'Backdoor' (called from get_access())"
In addition to the warning, it appears that due rw.map being overwritten (as explained in the second link), Read-Only memories can be written to via the backdoor, since get_access end up returning the default value of "RW". This appears to be in conflict with the Spec:
Researching this warning turned up a couple prior forum posts from 201