Helow

I am quite new in to sheet metal. I am having problem with unbending some parts. Zip file contains two parts that are welded together. The file with name kos1_2 can be unbent but the part with name kos1 cannot be unbent. Every time when I hit flattpatern button it say that this part contains feature that cannot be unbent. If you are wondering why I have such strange way of modeling it is becouse I find this way the only possible that can show me bend lines on flatpattern drawing latter.