Pretty simple bug to fix. @ symbols in emails are not escaped (everything else is though), so currently there is no way to use an email template with the new HiveOS UI as it causes connections to fail with a “Bad endpoint address” error (since the string ends up with two @ symbols). Instead, you have to manually set your email where you would normall have %EMAIL% and instead of @ escape it with %40.
would you be able to share a screen shot of your setup? I am getting the same Bad endpoint error