Offizieller Kommentar
Make sure you are not selecting areas that are outside the bounds of the reconstructed area that we provide. If you include areas that are out of bounds it will attempt to download elevation lookup tables that don't exist.
If one of the lookup tables is missing from your map for some reason we may need to reprocess it. It the tables are not available the tool will crash.
If you are making some really big measurements there can be quite a few files that get downloaded. We just did a test on one of your jobs and took a measurement around the whole perimeter and it took over a minute. Maybe you just need to give it more time.
We will attempt to give some sort of warning to this affect in the future.