Big luck!
New session! French Enable
Exactly the description that i made previous! Sphere etc...
I made a Sphere : some Curve iSo UV above - Kill the Sphere - Erase Top / Bottom calotte by triming Vertical curves by calottes
No Separate
Of course i save the file before launch the Distort Curves!
Moi blocked : only Alt + Ctrl + Del save the thing!

Have happy debug!

http://moiscript.weebly.com/uploads/3/9/3/8/3938813/bug_distort.3dm