Hi David --
I wasn't sure of the process you were using to add shapes. OK. Manual it is!
I was thinking that perhaps the file you are working in has some sort of corruption, so if you start a brand new Visio doc, that might eliminate the problem. The other possibility would be, that only the active page in your current document has a problem, so, by opening a new page, and all is well as you add shapes and exercise code, then that would tend to point to the problem being an issue with the page and not the entire file. The idea is to isolate the corruption to a page or a file, and then to see what (if any) code creates the problem. So, having said that, here's a rhetorical question: Can you start a new doc, and just use the shapeadded code rather than all of the pieces? Basically, start from a clean slate, then add one piece at a time. That way, you can track down the culprit. Perhaps it was something that happened as you were working/developing your code, and is no longer an issue.
HTH
Wapperdude