How to use OpenMTB Maps with 28.20

My custom maps are also built from OSM, and as said no problems this time for me. But agree that Garmin doesn’t have the best reputation 

Just to give another datapoint - every OSM based map I've tried works without issue. Freitzkarte, my own extracts from OSM, BBBIke.org monthly extracts or custom regions and themes extracted via their website. I'm also using a few local map overlays.

But this started to work when I've started to using Edge 1050 in a very specific way:

1. full factory reset with data wipe

2. connect via MTP and delete everything that Edge will let you to delete

3. update via Garmin Connect for PC, do not install garmin maps

4. set up as a new device via Connect for Android

5. do not restore backups, do not install anything from connect iq store

6. copy over your maps via MTP as .img files

7. make sure that the only .img files you have are your custom maps, basemap and dem layer. No climb pro and trailforks.

and you'll need to wipe your device periodically every 2-4 weeks or the crashes will be back. Had to do this 3 times during 13.14 firmware era.

It's also not 100% bulletproof, despite doing all this dance I still had a few random 'out of memory' popups followed by a crash. Suspiciously those happen in same few specific locations.

Yes, you can contact me. 

Yes, PC connection is possible. 

All actual Garmin maps, OpenMTB, OpenVelo.

Just riding, it crashes always at the same locations (MTB or Velo), if I disable the 3rd party maps, it works

You can contact me.

I am able to connect Edge to a computer

Maps installed: TopoActive Europe, MTK Suomi - Koko maa, TK_Finland, TK_Finland_polut, Trailforks

I was riding in groupride and after ~33 mins device crashed and started to boot loop. I was able to shut it down by pressing the power button and got it eventually turned on after some more boot looping. It stayed on some 10-15 mins and did same again. 

I have been testin and the proble is this one: TK_Finland_polut (might be as well TK_Finland, have not tested that yet).
At least for me usimng computer connection and just removing that file the crashing stopped (note this was only tested without longer nor riding testing).

With the polut file it either crash immidiatly when you power the device or when you go to map view (or try to move the map on that view).

It seems that the 28.33 update does not fix the problem, Trailmap (TK_Finland_polut) still goes to the infinite diagnostic loop. This has been working really well before 28.xx update (it has been actually working for years on 1030 and also about 1 year on 1050, so there still seems to be bugs on 28.xx 

I just tried the 28.33 and came to the same conclusion. Some OpenMTBmaps are still causing boot loops :-/

Regular reboots using TalkyToaster GB on 28.33. 
No issue prior to installing the TT GB map