On windows 10:
Had an issue with automatic install:
So, downloaded and install it manually but seems it's not signed? (Unknown editor):
PS: After all, 7.5.1 is running 
seems like the final windows install wasn't signed due to our recent installer building changes.
Will make sure it is fixed in the next update.
For now you can just ignore the warning and install it as you did.
Sorry @George, should have sent it to you privately
Fixed in Wappler 7.5.2