It was pretty easy to figure out, without going to any documentation. I had a list of 4,000 email addresses I wanted to send to, with some photos, and it was easy to write up my email, add photos, import the email addresses, and send.
The best part was that is worked flawlessly with my EIMS email server.
I tried another program which was cheaper, but didn't work well with my email server and had a hard time incorporating jpgs into my email.
I recommend MaxBulk Mailer for OSX.