For those that need to create follow-up tasks (or any other SF record) after a document merge is complete, you can utilize the Salesforce Process Builder to setup the automation.
**Note: You'll need to be using version 1.143 or later to use this functionality. You can upgrade via the AppExchange.
To get started, we're going to setup our Mapping in Salesforce. We're going to need the Mapping ID for the process builder, so copy that ID from the URL of the Edit Mapping page.
Inside the Process Builder (Setup > Create > Workflows & Approvals), we're going to create a New Process. We'll give it a name like Account Follow-up, then we want to start the process when a record is changed.
After you save the new process, you'll be taken to the Builder where you'll need to pick the object that you want to monitor. We're going to click the Add Object button and then select WebMerge Document from the list. We're going to start the process when a record is created.
Go ahead and Save that step, then we need to add a condition/filter because we only want to create the task for a specific mapping.
Click the Add Criteria button then give it a name. For the Field, we're going to choose WebMerge Mapping > Record ID, then we're going to paste our Mapping ID (from the URL on the Edit Mapping page) in the value box.
Next, we're going to setup the Action of our process. Click the Add Action button and then for the Action Type we're going to select "Create a Record". For Record Type, we're going to choose Task and then Salesforce is going to load a list of the fields on the task object so you can set their values.
You can set as many of the fields as you want, but the important ones are going to be Subject, Related To, and Due Date.
For the "Related To ID" field, you'll want to match it up to the Salesforce Record ID field on the WebMerge Document object. You'll use a formula field type and then just insert that field.
For the Dates, you can add a dynamic number of days, by using a formula value like this: TODAY() + 5 (this will add 5 days)
Here are our settings for the Task:
After you save your Action, you'll need to Activate the process and then you're done! Next time you generate a document using that mapping, it will also create a task!