How to connect the studio program to Orchestrator

Am trying to connect a studio program to the Orchestrator, it is opening the url which i had set in the assest field but it is unable to click on the web elements .

but am getting fault in orchestrator like


Try to Debug your Code, This error usually comes, when you are using a variable without assigning any value to it.

i just done the program to click on register button and fill the form by reading the data from excel and submit it. now i want to run this program in Orchestrator.
To open the url i created asset in orchestrator, to click on the register and filling the details using type into activity,should i create any asset ?