1. upload the image to your inventory in SIZE of your region
(e.g.: standard in 256x256 or 2x2 var in 512x512, etc.)
2. copy and past its inventory texture UUID into your Regions.ini
---> for example:
MaptileStaticUUID = c64a3590-f6c1-4e85-ae02-c778e3cb46fc
3. open your OpenSim.ini and set GenerateMaptiles = false
4. restart sim
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