I don't know exactly. eclipse tell me that are unresolved references, but i have imported all the libraries that i needs. I guess may be a wrong call of the methods. Can show some examples of these methods or link me a reference to the code?

I am writing a plugin, but I am not able to understand how I have to call HomeController methods. Every time I get a compile error. Who can give me a hint?

Well, browsing the source code I have found an attribute ID in object piece, but what I actually mean by ID is user defined ID. Namely an extra string field where a user can define an unique manner a piece of fornitoure and change if he will.

I would like to add a new field in the description of the forniture, indicating an ID of the object. How can I do this? Where I have to put my hands in the code?