World Partition Editor Minimap and large Landscapes

UE Version: 5.3.2
RAM: 128GB
VRAM: 48GB
OS: Linux

I am still trying to get the World Partition Editor Minimap to build in my project. I have a landscape with 32x32km it consists of 128x128 StreamingProxies (each with 250x250m)
Virtual Textures and Streaming are enbled.

I have learned that I have to add a WorldPartitionMinimapVolume actor to my map to build the Minimap. I put this Volume into the center of the map and scaled it on x,y to 16128 and 3000 on z so that it is as big as my map. Hitting Build->Build World Partition Editor Minimap runs for a few minutes then crashes.

Doing the same in the console yields following error message:

[2024.04.05-19.47.56:903][ 16]LogCore: Error: appError called: Assertion failed: (uint32)InDesc.Extent.X <= DeviceProperties.limits.maxImageDimension2D [File:./Runtime/VulkanRHI/Private/VulkanTexture.cpp] [Line: 235]

I used this command:

UnrealEditor MyProject.uproject MyMap.umap -run=WorldPartitionBuilderCommandlet -AllowCommandletRendering -builder=WorldPartitionMiniMapBuilder

UE seems to try to generate an image that is larger than 16383px, a size that vulkan cannot handle.

So I tried to scale the Volume down to 3000,3000. This worked, the Texture for the Minimap was built. I have found no option in Project Settings or the Details tab in the outliner for WorldPartitionMiniMap or WorldPartitionminiMapVolume to generate the map in smaller chunks.

I experimented with the World Units per Pixel and the Builder Cell Size settings to reduce the resolution of the generated Minimap texture. It works for my 3000,3000 scaled volume but not if I scale it up to include my whole landscape (16128,16128).

So I tried to scale my Volume down to 2016,2016, put it in the upper left corner and duplicated it a few times and put them in a row in an attempt to force UE to generate smaller images one after another and then merge them into a single image. This doesn’t work, it still tries to generate one too large image. So my question:

How can I build the Minimap so that it still stays within the limit of 16383x16383px?

My second question would be: When this works, how can I export the texture as a PNG, so that I can work with an external program with it and then re-import it again into UE?