Hi Mike,
I think you answered your own question by loosening the header support. Where is the header breaking? I'm guessing just in front of the support? You might consider a different type of support which allows more 360 degree movement.
How do you like the Topstar 110? I have a kit with the all balsa, built-up wing (still in the box). How does it perform with the YS 110?
Regards,
Will B.
PS Your Model looks very nice - what I can see!