How can I use a Form Type of Custom and a different Start Page. I see that they are options. Can you provide some details on how one might use these options. Are they for alternative form products?
You could use SharePoint Designer to change the default initiation form aspx page and add styling changes, but you change the fields and default values of them using the Workflow Initiation Parameters in the settings. For detail instructions see this link Create a workflow initiation form - SharePoint Designer
To create an initiation form for a workflow using Visual Studio, see this link Walkthrough: Creating a Workflow with Association and Initiation Forms
I would obviously recommend using Nintex Forms for this because of its details to the UI that can be added like validations and rules with ease and no code. I've found that the ROI is realized more quickly than you may first expect. Especially when you do not have to use SharePoint Destroyer or use a full time developer and qa to coordinate a build of a custom solution and then have to manage the code a few months from deployment because we need to add a new field. But then the developer is no longer working there, and the code is not in source control. Yes, I've been down this road before.
Nintex Workflow supports the use of either the Default form (which is an .aspx form provided out of the box and is not editable by end users), an InfoPath form (which is editable in Microsoft InfoPath 2013) and Custom (pre-developed .aspx) forms. You can change what is on the start form also through variables within the workflow as they can appear on the start form to get start data. The page you are viewing as you start a workflow manually is a Custom form.
Also, Nintex Forms can be used to edit and design workflow start forms and task forms from within Nintex Workflow. To design forms using Nintex Forms in Nintex Workflow, the Nintex Forms for Nintex Workflow site collection feature must be activated.
The following Nintex Workflow forms can be edited using Nintex Forms:
Thanks for the info. I would like to build a Custom (pre-developed .aspx) form. Can you provide the guidelines that are necessary to make it compatible?
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