Office Connector does not render the first slide of a ppt/pptx

If you try to view the first page of a ppt/pptx using the office power point macro you will get a broken image error instead of the first page.

Steps to Reproduce:

1. Attach the test file "Ninjas.pptx" in a Confluence page.
2. Then use the office power point macro to display the attached ppt.
3. Use 0 as the "Slide Number" field.
4. Save.
5. Note that you will see a broken icon page instead of the actual ppt first page.

Notes

The ppt/pptx files always start at slide number 0, if you use 1 instead of 0 in the above test you will see the second slide (the image of a ninja) instead the introduction slide (Ninjas do they exist?).