It looks good to me... and a beautiful mural painting indeed.
As a ptGUI user... i would try ptGUI
For me it is the most flexible program around for panorama's as far as i know. It is for me one of those programs so well made that it deserves it to be learned. ( like Photoshop )
You can use different lenses , mix vertical and portrait images and even different waypoints up to some degree...
If a stitch goes wrong ; you can manually change things till it works.
In this case- treating the images as scanned images- i would manually choose a long telelens ( 2000mm) and start from there...