A Landscape Material I use currently has 12 textures (6 Diffuse, 6 Normal) and 7 layers.
When I migrate the map to a new project (for a quicker build), the landscape texture limit of 12 is reduced to 10 (not 11). I refer to [this answer][1]. With more than 10 textures, the Landscape Material will not compile for that section of the map. The Default Material is used instead.
An warning message is produced.
PackagingResults: Warning: Failed to compile Material {path/to/material} (MI:{path/to/heightmap}{:PersistentLevel.LandscapeStreamingProxy_0.LandscapeMaterialInstanceConstant_276) for platform PCD3D_SM5, Default Material will be used in game.
To fix this issue, I removed 2 textures (1 Diffuse and 1 Normal). In the following pictures, you can see the sand textures performing double duty as the gravel path.
Original landscape (12 Textures, 7 Layers):
Landscape after Migrate (with compile warning)
Landscape fix (10 Textures, 7 Layers)
This project was updated from 4.24 to 4.26. And due to issues with the Water Plugin, I checked and then unchecked the “Use Landscape Layers” box. I had also experimented with both forms of VT, but abandoned that. All this was done before migrating.
Finally: The heightmaps did not migrate with the map, I had to migrate them separately.