Your UMO looks great, with the side panels and the magnet idea, love the idea, so I'll make something similar.
Then I'm also interested in the solution that you made with the cross-flow fan. I was wondering if this works good. So I would also like to a cross-flow fan, instead of closing the top of my UMO+.
Could you tell me which cross-flow that you used and if you bought it somewhere online?