BUMP - trying to raise awareness for this since it still might be an issue.
@[deleted] - you shouldn't get a long spinner - at least not the 10-15 second kind.
If Upcloud is involved, that might be the issue... well, not Upcloud per se, but some issue Vlad isn't aware of interacting with those servers.
If you install Aware locally on a PC, and use the CRM test, you'll see there is no spinner - it sends immediately. If your (or anyone's) users are having to wait to send individual Emails - thats wrong!