SmartObject Failing with Required Property Troubleshooting
I have seen this issue a whole bunch of times and it can have very many causes. The error usually looks something like: "SmartObject Method Update has required Property ID."
Smartform/Workflow Designer Issue.
Make sure that there is a Value being passed into the method that is failing.
Make sure that this value is populated at the time the method is being called.
If neither of these, move on to Cause #2.
If you don't think that the property giving us the issue should be required, check your SmartObject and see if the property is required there.
This can happen a lot with SharePoint solutions because for most of the methods, the Document/Attachment could be required for most methods, but for some it is not. If the property is required, you will get this issue.
If neither #1 or #2, move on to cause 3.
This issue is usually seen when it comes to SharePoint as well. For example, the SharePoint call cannot be returned by the time Smartforms/Workflow needs the property.