Following these instructions, you can get 4.6 to install successfully.

http://www.mitchelsellers.com/Blogs/tabid/54/articleType/ArticleView/articleId/143/Installing-DotNetNuke-460-Locally.aspx

When I view the site, it is something like http://localhost:2269/DotNetNukeTest/Default.aspx and all works fine.  (I made it use a static port so it will always be 2269).

So far, so good.  Now, when you login as host and click on Portals, you see the portal you just created in there.   It has something called 'Portal Aliases' and it is set to "localhost/dotnetnuketest".  Note, it is missing the port - that means if you click on that portal alias, it opens a new browser window, which of course does not work.

I think it is there that the problem starts.   Now, if you create a new portal - a child one - it will show the portal alias as "localhost:2269/DotNetNukeTest/", which is right and you can add your new alias on that and come up with "localhost:2269/DotNetNukeTest/NewPortal".  After you click 'create portal' - you end up at a 'page not found' - because it tried to redirect you to http://localhost/dotnetnuketest.

Going back to Portals, you will see your new portal listed, with an alias of "localhost:2269/DotNetNukeTest/NewPortal", which appears to be correct.  However, clicking on it you end up at http://localhost/dotnetnuketest again.

Clearly, this is some sort of bug or lack of support for child portals in the built in webserver or something.

Any ideas?