Change Joomla script component

Hi, This project is for a php programer. I have a Joomla component: beestoworkflow. Is working ok with joomla but i need to make some change in the code. Please see the component before you read the project to know what I am talking about. The component is for Joomla 2.5 and I attached the file in this project. Actually the software works with two leves of access. What I need is to create a new level of access, so we can use three leves of permissions: Manager: can create, edit, delete, list and all the actions for the projects of all the staff members and can assign this proyects to a client and to an staff member anytime. And also this level will be the only one with the permission to make,edit,list,etc. the system workflows. Staff: Can see his own projects and can: edit, work in, create, delete, list all the tasks for this proyect. They can not create, delete or edit projects. Client: Can see his own projects and can see the task evolution and informs. And, he can write a message or note to the staff asking for some request. They can not request projects. You have to put in the offering the text: "lo he leido". To make sure you read the text. The others features can stay the same. Is just change some permissions and include a new user level. If you see the script you will notice that is simple if you have php experience.