We just released Maps Marker Pro v4.0.2 which fixes an issue with popuptext not being loaded correctly in TinyMCE visual mode on some sites. Additionally we also also re-added the missing setting for marker cluster radius amongst other minor usability improvements.
If you did not update from v3.1.1 to v4 yet, please see the release notes from v4.0 for installation instruction, migration tutorial and post installation tasks.
If you still experience any issues, please submit a helpdesk ticket.
Happy mapping!
Changelog for version 4.0.2 - released on 26.10.2018 (release notes)
 | allow upload if upload limit cannot be determined | |
| move setting for maps in tabs to simplified editor | |
 | popuptexts on marker edit pages could not be loaded in TinyMCE visual editor on some sites | |
| add missing setting for max cluster radius | |
| add missing translation for Save Button | |