One thing that got me hooked on Visio from the beginning was that you were not limited to the shapes that were supplied by the product, You could create shapes from scratch, modify existing shapes or wrap an image from any source into a Visio shape. So, I am always on the hunt for new shapes that are available on the internet.
Recently, I came across a set of well made shapes and was able to get in touch with the creator. Though the shapes looked good, they did not have any of the smarts that can be associated with Visio shapes. The Visio shapes were just foreign images that could not be changed or coloured. The shapes were originally created in Adobe Illustrator and imported into Visio. I tried using other export options from Illustrator, but none allowed me to ungroup the shapes in Visio so the shape can be disected into individual elements that be recombined.
Thanks to Enric Mañas, a PowerPoint MVP, I found out that it is possible to disect the shape by using PowerPoint. The file needs to be first saved as an EPS in Illustrator. The EPS file is then inserted into a new PowerPoint slide and then saved as a WMF file. The WMF file is then inserted in to a Visio drawing and this new shape can then be ungrouped.
So if you need to manipulate a shape created in Adobe Illustrator, use PowerPoint to convert an EPS file to a WMF file.