Create a new tree structure (the actual one does not totally answer my needs)

Actually on my personnal website that I use to do statiscal calculations, I already use a tree structure to proceed some calculations. The problem is that this actual tree structure doesn't let me do exactly what I want to do and it cannot be optimized because of the language used (javascript) using a dhtmlx framework (with scripts not commented nor documented). Today, I need to refound my software to be able to do all calculations I need. I wait for your solutions propositions. All details of my new sotware are documented in the attached file « How the software must [login to view URL] ». I think you would be able to win time (by using some already written scripts) to developp new ones. Here are 2 scripts in which there should be the actual calculation "[login to view URL]" and [login to view URL]". ** Note ** I prefer to work with Freelancers who only work for themselves and their clients. Like that we can communicate all the day and it is also a way for me to be sure that the job is done fastly and carefully. I need scripts to be well documented and commented to explain the logic used. I need the scripts installed on the server to be sent to me by email too. ** Thank you for your comprehension **