It works for me. I downloaded it from a link here https://www.openstreetmap.org/user/Richard/diary/395259
when you run it you get a world map. Either map.One option is to zoom all the way in.. which isn't so convenient, or open convenient. A better solution is zoom into the map as we did with Potlatch2 then reduce this window to a new half screen. Start Potlatch3 app and reduce that window to the other half of the OSM map page screen. Go back to the zommed window and do as SimonPoole suggests. click on the emote edit box. The Potlatch3 window will then be in edit mode, change it to full screen and it just like P2. See JPEG
![alt text][1]
[1]: https://help.openstreetmap.org/upfiles/Potlatch3_windows_start.JPG