So came across a scenario this week where I needed to display a lookup column from a SharePoint 2010 document library in the Document Information Panel in Word and allow access to the object via Quick Parts and not Custom Document Properties. I created the columns and associated them with the SharePoint List/Content Types and they were available in the DIP. Easy enough.
Not quite, as mentioned in this blog post from last year. When a user selects a value from the lookup column from the DIP, and then the object is added to the Word Document, the value from the lookup column displays. However, if it is changed or is referenced by an object prior to selection, then it shows a number instead of the value. The number is the Item ID from the list the lookup column references. The post I just mentioned explains how to work around this issue. Basically, using InfoPath, you can customize the DIP and create a read-only field to perform a filtered query on the list based on the lookup column selection. You use the read-only field as a quickpart and not the lookup field itself.
I discovered an interesting, but not surprising, undocumented feature when performing this task using InfoPath 2010. It doesn’t work. Office 2010 will recognize the changes, but Office 2007 does not like it. Even if I saved it in compatibility mode from InfoPath 2010.
So hopefully the half a day I spent working on this issue can save someone else a few hours. If you run into this issue with SharePoint 2010 and your users will potentially access the documents with Office 2007, make the changes using InfoPath 2007. Both Office 2007 and 2010 will recognize the changes.