For XML error - I don't see it in current development version log, so changes are that it's already fixed, pls double-check when v.6.2 is out.
For MIB error - I guess MIB compiler is failing on some specific MIB file. You can try removing some of your MIB files until you find which one is causing the issue (you can remove half of them, recomplie, then another half, etc...). Or you can just share your whole MIB file collection.