Hello Allin

I have been doing further tests over the past couple of days. The good news is that with MAPC2MAPC I can make a two-level JPX with the 1-25k and 1-50k layers of raster maps, set the zoom levels in JNX Customizer and convert this JPX to an IMG. This IMG can be viewed in BC and on my device, and changes between the 1-25k and 1-50k mapping according to the zoom level as expected.

The bad news is that if I make a separate JPX for each, choosing the same zoom levels as before and convert to two IMGs before joining them in GMapTool to a single IMG, no matter what settings I adjust, only the 1-50 layer is ever visible in BC or the device when fully zoomed-in. I have tried various zoom/scale levels in creating the JNXs and in GMT, changed the draw priorities, tried a few different TRE parameters (Map Series IDs). I must be missing something important or maybe I am bumping up against a limitation of Alex's method as mentioned in post 1?

Have you been able to able to do this conversion with two separate raster JNXs?

Eyelet