I'm sorry you didn't receive a reply. I've been away from the forum for a long time (returned to my former (non-MATE) distro.).
Just popped on to perform some maintenance and spotted your question, even though it was posted many months ago I don't want you to think I was ignoring you. Since no longer using MATE, I'm sorry I won't be able to test solutions for you, but do hope you managed to find an answer elsewhere!