Short answer: Use this link and enter relevant information. See http://slicer.kitware.com/midas3/slicerappstore/?os=win&arch=amd64&revision=&search=&layout=layout
Long answer:
- The landing page is trying to find the most recent Slicer revision … but this is not done efficiently.
- We have plan to modernize the infrastructure and address issue like the one you reported. See https://www.slicer.org/wiki/Documentation/Labs/ExtensionsServer