Custom overlay settings are not being saved to the cloud account.
Yesterday was the third time I noticed this bug.
I flushed the cookies and cache yesterday and (once again) I found that when I logged back in to Windy my overlay settings were all older developmental versions that were valid around six weeks ago.
i.e. The new settings had not been saved to the cloud since then.
I other words Windy is not saving overlay changes to the cloud at all, it is only saving them to my local-computer's browser cache.
So when I flushed the browser cache (Firefox 63.0.3) the Windy overlay settings are gone from that point, and the ones that are reloaded from my Windy 'cloud' account are all much older versions, than those that should have been stored in there.
So when you log back in you have to manually reload all the custom overly settings back into each and every overlay once more (hmm ... fun).
You think they're being saved to the Windy Settings 'cloud', but they just aren't being saved there at all.
So there's not a lot of point to new users obtaining a Windy account if the cloud settings aren't being saved to the cloud and you don't have the re-loadable back-ups of your setup that you believed you had.