So I install/Europe. Had a fair few issues with the clone- the scripts aren't the most resilient as had to delete a few folders and reinit - but eventually managed it. I can't really say much more about the process of cloning - it wasn't as easy as I'd hoped but not an insurmountable problem.
Starting at my favourite airbase (LSGS) and flew one of my standard routes around the valleys. Unfortunately there are some new problems with the mountains.So I tried a few other locations and there are definitely some bugs in the terrain mesh building.
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Didn't manage to figure out how to get the OSM buildings; and I miss these as they add a lot to the visual experience.
Over London I found another bad seam.
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I will be continuing to us TG for a while so I can properly evaluate how it works for me; at the moment I'm disappointed with Sion because the mountains are the best part of Switzerland.