Cricut design question

I am starting to use a cricut for cutting out cardstock buildings. I design the buildings in shetchup 2d, export as a .png file and import into cricut. For instance I have a design for a wall which includes windows which will be cut out and lines which I want to score in cricut. I have no problem with importing and cutting. The problem comes when I want to score lines. When I import the .png file the first thing cricut asks is for me to identify what I want cut out. When I do this the entire wall, except or the windows turns black and I cannot see the lines on the .png file which I want to score.

Any ideas on how to work around this problem?