Automatic Email Manager works fine with any receipt printers (ticket printer) at the condition you use the original Windows printer driver from manufacturer and not the generic text driver.
Now please edit the scenario which prints, in Automatic Email Manager:
1. Edit the print action (print email body and/or print attachment)
2. Click on 'Settings' (at right of the printer name)
3. Now unset the option to use default printer settings and set the printer as you need, especially the paper size
4. That's all, Redo a test
If the problem persists after these settings we suggest you to contact us here.