When you activate the Workflow or Conversations features of Sintel Forms the add-in automatically creates 2 lists to store the data for these features. Depending on how complex your workflow is or how much you use the conversations feature, these 2 lists can store quite a bit of data for each form over time.
Due to the quantity of data being stored and SharePoint's list view threshold, you may encounter issues whereby one or both of these lists might grow too big, which could result in SharePoint preventing access to them.
Starting from the August release (v. 1.14), we have introduced a new mode for storing workflow and conversations data. This will avoid the issue relating to the list view threshold and to improve general performance. With this new mode the data within these 2 lists will be stored in sub folders, meaning that for each form that is created an associated folder is created within the Workflow and Conversations lists.
All forms created after the 1.14 release will automatically use the new folder-based mode by default and any forms that were created before this date will require their mode changed.
Changing over to the new mode is easy. Simply launch the Sintel Forms Designer and it will detect if the the mode needs to be changed. The user can choose to proceed to change the mode or remain in the old mode. If the user chooses to convert to the new mode the process should only take a few seconds and once it's completed the user can proceed to exit the Sintel Forms Designer.
It's important to note that the conversion process does not modify the form itself nor any of the data stored within the form. The new mode is simply intended to avoid potential issues with the list view threshold in SharePoint.
When you switch over to the new mode it automatically enables cascade deletion on the Workflow and Conversations lists such that if a form is deleted then it's associated workflow and conversations history are deleted. Also to ensure good housekeeping, any orphaned entries found in both the workflow and conversation lists are deleted during the conversion process.