Hi David, I have gone through your requirement. I came to know that you need a setup file (for the power point add-ins) which when installed in other systems, they should get updated with the Add-Ins available in the set up file.
I'm having 8+ years of experience in windows, web and database application development using Microsoft dot net technologies(VB.Net/C# etc..). I have enough experience in creating various set up files for different Out look add-ins, word add-ins, windows services etc.. (similar to yours requirement).
If you are interested, please do let me know so that we can discuss more elaborately about the requirement and can arrive at the accurate time lines and cost at our ease.