I was wondering if anyone has managed to get the Offline Maps feature to work

I'm flying a M2P with Android and have all the latest updates installed.  I have used the offline maps feature in the Go 4 app to download a map of my local area and that appears successful as my map shows on the list as 77Mb and I can see the area it covers.  But if I fly with no wifi or cellphone data access then the map box remains just black.

Have I missed something?

Sounds like you did everything right. It works for me. Strange thing is that your mapbox is black.
If I fly in offline/airplane mode without having a map downloaded it's a bright map tone.

I cant even donwload a map on android, it gets to 22% everytime and then shutsdown and tells me to delete whats already there.
So i can delete and it will download again and once more stop at 22~ %

I had that problem and found out that my map setting was on satellite or hybrid mode.  You might try this....bring the black map up in full screen and make sure its set in normal/regular map mode and not hybrid or satellite.  That's the only way I was able to get offline maps to work on my Android..........

Thanks everyone. And yes, Sato has it right.  I normally run hybrid or satellite view because I'm in a rural area (not many streets).  Switching to normal map works however you have to do it beforehand on a working online map otherwise the view remains black. Easy to get caught out if moving to an area with no data connection even if you have the offline maps ready to go.