Starting from atlas 12 Lowrance defines 4 types of raster maps:
www.tacklefever.de/index.php?topic=6168.0
And we can have 3 raster layers in one map:
1. Shaded relief - visible if we select Shaded Relief in device.
2. Satellite imagery - visible as Photo Overlay
3. Raster nautical chart - visible if we select Raster charts
I've asked about 3 - it works only with additional key in atlas description string:
www.tacklefever.de/index.php?topic=6169.0
So if we select raster output and raster chart type of output, we need description string in the IMC project to looks like
"M=My awesome map|DVOR=TRUE"