Is there an API to add a page to the System Properties tab of System Options, containing 3rd party options ?
I am about 99% certain the answer is 'no'. You will need to handle these options within your add-in.
SolidWorks API Tutorials
Why don't you add a command manager group with a settings dialog form as item?
This is pretty much what I did and it works great.
Thanks, Christoph, that's another good option.
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