The Learning Curve

Sorry but no pictures today.
I've done a fare amount of work on my crossbow today, but most of it has been done in my head.
I started the inital layout of the dry-fire mechanism, which is going well. Its a top mounted dry-fire, made from aluminium.
I concidered a bottom rail mounted dry-fire, but gravity is working for me on a top mounted version. In my opinion though, an aluminium string catcher, (essentially what a dry-fire is) Is more of an anti-go-off-half-cocked device, rather than a dry-fire device.
The dry-fire device should be a secondary safety-catch, which would stop you pulling the trigger, unless a bolt is present. (Only my opinion).

There is a few things you must realise about me. That is I have NEVER fired or even held a crossbow before. All my small amount of knowledge has come from the net with hours upon hours of reading.
Many many moons ago I served my time as an apprentice cabinat maker, so wood is no stranger to me.
Engineering and design has always been a passion of mine, and working with my hands is a pleasure for me.
So any points I make here is through my experiance building this crossbow.

With the exception of the Prod / Limb, I intend to build everything I need / wish to have for this crossbow.
Which includes the Bolts (I will buy the shafts), Quiver, Case, Red/Green-dot Sight, Laser Boresighter, String (I will buy one for reference),  

I do like Jasonwemp's idea of adding a switch on the stock for the Red dot sight. But I thought I might try and take it a step further, and add a capacitive touch circuit to the aluminium trigger. So the second your finger touches the trigger the red dot sight will turn on. (More of a gadget than a necessity, but might be fun).

I have made some mistakes within this build, but its all a learning curve to me.
When the build is complete I will go over all the mistakes in detail and how to overcome or even, not make them.