The problem may be caused by the comma in the free-space's name. I believe the comma causes a conflict when you attempt to connect a free-space to an image as the system interprets the free-space name as two page names and is unable to find the correct free-space to attach the image. (...non-tekkie explanation...)
You can create a new free-space that doesn't use a comma (you can then merge the current free-space into the new free-space to delete the current free-space) so you can attach the image.