In general, the only issue that will cause a listing page to load very, slow, not load -- or display a 504 error -- is the rare case when it takes ShowMojo too long to calculate the available showtimes for a listing.

No one item below will cause this issue, but a combination of these factors is most likely the cause:

1. More than 30 weekly recurring showing windows on a calendar related to a listing.
2. Calendars that allow showings more that 30 day in advance.
3. The same listing assigned to more than four calendars.
4. Enabling Autonomous Scheduling on the calendar.

To resolve the issue, update the relevant ShowMojo calendars (on the Calendar page) to reduce any of the above factors.

If you encounter (and/or resolve) this issue, please Contact ShowMojo Support‍ with as much detail about the issue as possible.