We also upgraded to 4.7 recently. I don't know if this will help ... There's a relationship between Roles and Profile Properties. I've added three custom fields for User Profiles. When attempting to Manage Roles for my users, I get an error when data has NEVER been added to a user's custom profile property. Once data has been entered for any one of the custom fields, Manage Roles works properly. It also works properly after removing custom data.

The only way I was able to successfully install dotnetnuke was to have a completely clean database. I had left some of my own tables in there with previous tries and it failed every time. If you haven't tried that yet I would give it a go. You need to have

Open Microsoft Sql Studio Management Express in summary view, then back up your database. Then select all the tables and stored procedures and delete them. You might have to repeat the delete as some dependencies prevent root tables from being deleted all at once. Go to .../dotnetnuke/install/installwizard.aspx .
That worked everytime for me.