Hey Edmek, when importing characters you need to use the following settings.
Grid by Cell Size (in the drop down)
Pixel Size - X:16 Y:24
Offset - X:0 Y:8
Padding - X:0 Y:8
For the building items the following appears to work.
Grid by Cell Size (in the drop down)
Pixel Size - X:16 Y:16
I need to do some testing as I only downloaded this 5 minutes ago