Is it possible to customize the startscreen when a workflow starts on a conditional variable?
I would like to add/change some text on the Original page (see attachment).
right now there is no such option. There are several requests on uservoice where you could throw your votes at:
Modifying the start form would really be helpful. As a workaround right now you could only create a list and modify its form. After entering the data in the form a workflow kicks off, working with the data entered in the list. But this is not always a good solution and results in using additional workflows / lists.