Thank you for contacting support. Please note, the Text element of a shape has multiple character rows (a.k.a Char) and each cp tag represents the properties of a character row. In your source Visio diagram, there are 4 character rows and 4 cp tags. The two empty lines don’t mean the lines of text. It is a line break element. The complete string is as follows: “Vendor Scheduling\nPP14 - Vendor Material Planning\n”
I’m not certain about the possibility of some text without the cp tag. However, Aspose.Diagram API mimics the behavior Microsoft Office Visio. So, please refer to the following Microsoft help topics: [Working with a Shape’s Text in DatadiagramML] and [Manipulate the Visio file format programmatically].
Please let us know in case any further assistance or questions.