For those who would have the same problem as me:
I had problem with open street map which was not displayed.
the solution is below:
switch to advance mode then go to settings/layout/page only find this section: </section>
{has_location_venue}
<section class=”em-event-location”>
#_LOCATIONMAP {100%,0}
</section>
Put a space between #LOCATIONMAP AND {100%,0}
and you will see the map appear in your pages.