Help! move objects with custom attribute holder

Armabelico

Hello, I'm having this problem trying to move an object on it's Z axis using a custom attribute holder but instead of moving it on it's local coordinates it moves it to the coordinate number present on the custom attribute holder. I made a video which I hope explains better the situation.

https://www.youtube.com/watch?v=b2EP_L26_m8

I'm wondering if it's better to use an expression or if there's a method to wire it to the local coordinates, anyway I need to make the local coordinates available and I don't know how to do it.

If someone can help me or point me some stuff to read and learn .  

Thank you guys. 

Cheers

Armabelico

Hello again I made a vital change on the model cause I found out that the proportions were incorrect so I made a bit of research and found a diagram with radius and meassurements for it and changed it, now it should work but I'm still having the same problem with the rigging part.
 
the lower part works but trying to rig the upper part it isn't going very well. I added bones and set Ik solver and bending direction towards a helper but It began to twist and locking/disabling axis isn't working. I'm using 3ds max btw any help or guidance will be appreciated. thank you

monster

Freeze Transforms on the model that will be moving. The wire the Zero Position X, Y, or Z. This will move it on the local axis starting from the frozen position.