How can I hyperlink to PowerPoint so that the PP plays instead of opening in Design mode

Question

As per the title, I have a number of PowerPoints that I need to publish on an Intranet site.
The problem that I am having is that I do not know how to publish as a PowerPoint Show.

I want the users to click on a hyperlink on my asp.net page which will then open and play the PowerPoint.
I have tried saving the pptx as pps and ppsx - when I opebn the files directly from the foler, then they auto play and I do not have access to the design of the PowerPoint.
When I hyperlink to the very same files and click on the link, they open in design mode and do not autoplay.

Alternatives that I have tried include:

• ppt to flash converters, but the results are very poor (incorrect) and most of them are not free.
• converting to pdf which works well, but many of the ppts include animations which obviously do not transfer to the pdf
• converting the ppt to video, but this results in large file sizes (50MB+ in some cases)

Thanks

Gary