Custom header and inputs on tree timeline



I am currently assessing libraries for creating timeline with drag and drop feature, just like what DHTMLX did. But, I found out that I can’t get example code for example in link I am trying to build timeline like in the attachment. If yes, can I get the example code for that purpose? I will need to decide in these near few days weather to buy the pro version of this tool or surfing for another options. Hopefully DHTMLX can fulfill my requirements.

Thank you.