I can't find the URL to share the mailer to others so they can approve it before sending out. Using the owners email does not get them a live sample of the mailer - it goes to spam or does not get there at all.
URLs are only generated for emails after they've been scheduled, and are not actually live and accessible until after the email has been truly sent.
I was able to test send your account's emails and receive them in my regular inbox right away, without any issues. However, I am not your account owner, which is what your email program is likely having an issue with. When you send an email to the sending address through us - test or otherwise - it has the chance to trigger a warning message or be spammed out depending on your email program's settings. This is because it's an email being sent to you, claiming to be from yourself, but actually coming from a different source (us). For you, it should be as simple as dragging the email into your regular inbox to teach your email program's algorithm to trust it.
Here are somegeneral best practices for deliverability. Deliverability can have a lot of variables, from elements on our side, on your side, on the recipient's side, and in their email system company's side. It's also a generally good idea to set upself-authenticationsince you're sending emails using an address that has its own domain, rather than a free one (Gmail, Live, Yahoo, AOL, Hotmail, Verizon, etc.)
If you'd like to learn more about safelisting, and what it entails: