@Paul Widenka Apologies for the delay in response and all the inconvenience caused because of the issue.
By reading the above problem statement, my recommendation would be to use fixed/nominated port for it so that you do not have to worry about context path to each URL. Moreover running locally or on fabric, it should run at same URL's so that any issue can be identified during development only. This is just personal recommendation basis the situation which you are running into.
However adding manually "/MyServiceName/MyApplication/Help" in the asp page should work generally, what is the url it is trying to load when you click on this link after deployment? This might not be working locally as it could not be resolved locally but should work once you have proxy configured for it.
Another approach which you can use it to rewrite the request url at the proxy level to append specific path before routing it to appropriate service or so.
But I won't suggest using this approach as it would be difficult to identify the request originating application and better approach would be to use different port for each application so any context switch (url rewriting or other filteration) can be done at proxy level.
Hope this helps.
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