When adding a Map Overlay, the file must be in the MBTile file format. You can create MBTiles using the Maptiler Desktop app which can be downloaded for free here - https://www.maptiler.com/desktop/.
Once you have downloaded, the Maptiler application you can convert your image, whether it is a JPEG, PNG, etc, into the correct format.
To do this.
- Drop your image onto the Maptiler desktop app.
Note: You can also select Open file
- Once you've dragged a file to the Maptiler app, select Assign Location Visually (GeoReferencer).

Two maps will appear, one of them is your image and the other is Maptiler app map. - On the map on the left, find your location. You can use the search icon if needed.

- Once found, you can change to satellite view to match the two maps up. This will make it easier to match your location.

- Select Google Map - Satellite

- Click on a point on each map to create the first pair of the pairs of location points.
Note: I will select three pairs of location points, however, you can select more than three location points.
- Select the remaining location points.

- Select Overlay to place the two maps on top of each other.

- Once happy, click Continue

- Click Export.

- Click MBTiles and then select Continue

- Modify the Output tile format and Zoom levels.
- Select Render.

- Navigate to the correct folder and save the MBTile file in that folder.

- Click Continue

The MBTile has now been created and you can find the file in the location displayed. It can now be added to ScaffoldIQ.