Here is the improved 3D printable M200 battery cover: https://www.thingiverse.com/thing:4508352
I have made the side tabs a little more robust with a larger radius fillet, increased the clearance of the short edge tabs, reduced the width and length vary slightly for easier fit, and added some rib cutouts to make a finger grip area for opening the cover. The new model came off the printer and went right into my M200 without any post processing other than removing the small amount of support material under the hooks and tabs. I have also added a second model which is a stabilizer part which will protect all the hooks and tabs if the cover needs to be mailed. If you need a cover and don't have access to a 3D printer contact me and I can send one if you cover the shipping and material cost.
