Please help with my "How to build a Trebuchet" Survey

I'm wanting to publish a tip book about Trebuchets.

I know I had a lot of problems with my first Trebuchet, and I wish someone had shared with me some tips to make it easier to build and launch further.

Will you please share with me the challenges you've had with a Trebuchet?

If you include your email address I'll send you a copy when it is done.