Garmin Montana not showing downloaded OSM of Bali

Hi again.
I have a Garmin Montana 680 now, having replaced my 76CsX. I have 3 maps seemingly available to me when I go to Setup>Select Map. These are Worldwide DEM Basemap, TOPO Australia & New Zealand and Digital Globe. All have “Enabled” alongside.

I wanted more detail on Bali so I requested a Bali map by selecting Indonesis from the server. Got it OK and extracted it.

Placed it in my Garmin directory on the unit and nothing showed.

I had no SD card in the unit as I was told to not use one for geocaches so I waited until I returned home to WA and put a fresh SD card in the unit’s slot. I had created a directory Garmin and put the unzipped file into that directory.

Still didn’t show up.

Noticed that the file was called gpsmapsupp and surmised that the unit would perhaps be looking for a file with “.img” as a suffix to I renamed the file.

Still no change. Map does not show up on the unit and there is no more detail on Bali than there was on the worldwide default map.
Can anyone point me at what I am not doing correctly?
thank you

Hi Hoges. There is a “Garmin maps” sub forum on this board. You might already find your answer there.

Thank you. Shifted it over to where you said.