Thanks for the quick reply, Bethnor. With your comments in mind I will give it another try.
bethnor wrote:... really suggest is to follow exactly what folds are valleys and which are mountains.
I believe that I did all the creases correctly. Only on these flaps, the diagram is a bit unclear. It seems that there are no folds in this part.
bethnor wrote:...the lower arrow is in the first photo should NOT be squash-folded...
May I conclude from that sentence that the
upper arrow part flap does needs to be squash-folded? So, after flatting the model, the upper arrow flap results in a symmetric part, while the lower arrow flap is asymmetric? Thanks!