If you first create your design and then afterwards change your plan image size or layout, you do not need to redo your design. Simply open the modified plan image by using the Browse button in the Import page, then go to the Design page and use the Scale tool to set the scale of the new image just as you would normally do. Once the scale is set, you can reposition your entire design relative to the changed floor plan in one action by using the menu item Edit -> Select All and then doing a normal drag. Although only those objects corresponding to the current tool tab will be shown as selected, Select All will select all objects from all tabs in your design, and allow them to be repositioned as one.
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