Whenever I add folders to my shares, I cannot use the link to browse my own folder view what the remote viewers would see if they clicked on that link. It times out, reports user offline or such.

Fopnu User attempts to view their own remote shared browsing link
Searching for peer location... then... Fopnu reports Remote user is offline

somebody else wrote on similar thread:
https://forum.fopnu.com/support/510
NAT on your router (or your ISP's router further down the line) should be configured to enable so-called hairpin traffic (from the internal network addresses to external addresses assigned to them, then back to corresponding devices). Without it, you are only able to check your client from a different ISP