It should have Nothing to do with connection errors to the net. But, s3d shouldn't have gates to jump through like signing in to use non-cloud based software...
Call it my error or a 'Senior moment'. However, not knowing the guts of S3d I posted the only other element of communication in the software - call a 'Stab in the dark'
Having demonstrated my stupidity, I'll tell you how I stopped having the same problem on my two iMacs (one with snow Leopard, the other with Sierra):
Once logged into s3d and successfully booting s3d, I turned off all connections to the outside world using the software "Little Snitch". I don't use the 'Check for Updates' I simply login to the site and download. I learned to never update s3d until days after the release and reading about the new bugs...
screenshot of of Little Snitch's Monitor panel showing s3d is blocked. The important thing is getting logged-in, booting the software, and never letting it communicate again with the s3d site. discovered this solution 4 years ago and haven't had the problem since...
anyway , apologize for confusing you....
[EDIT] added screenshot showing no longer logged in yet, s3d still working (because it can't connect to site and get connection error)
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