On looking into it further, I noticed something. I am not sure if this has anything to do with the issue, but I thought I would mention it. When I originally ran the Installation Wizard (with the original web.config in place), the wizard said that my database connection tested succesfully. I clicked next and got caught in the 'Installing Scripts' loop others mentioned. When I looked in the web.config, I saw this line:
<add name="SqlDataProvider" type="DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider" connectionStringName="SiteSqlServer" upgradeConnectionString="" providerPath="~\Providers\DataProviders\SqlDataProvider\" objectQualifier="dnn_db" databaseOwner="dnn_usr" />
After I did what I outlined in my previous post, that same line now says:
<add name="SqlDataProvider" type="DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider" connectionStringName="SiteSqlServer" upgradeConnectionString="" providerPath="~\Providers\DataProviders\SqlDataProvider\" objectQualifier="dnn_" databaseOwner="dbo" />
Just to be clear, my user (dnn_usr) is set up with dbo rights and is the database owner, but it still would not install. I am too relieved to have finally gotten it installed to uninstall it and see if changing that line in the original web.config would allow it to install properly. I hope all this helps.