Gantt LightBox requirement

I want to use Gantt Chart for my project. I had gone through documentation but still not clear on various aspects.

  1. Can I show customized light box? for example, on click i wanted to have a light box with the tabs. each tab with different content. One of the

  2. I want user to manipulate everything in the browser and then save entire grid/chart in the DB on click of “Save”. Is this possible?

  3. Can i hide “+” icon (Which adds new task and present on each row) on second and third level of grid?

Any help is greatly appreciated.
This would help me taking decision to use dhtmlx gantt in our project.