Unable to install the UI with DW with the Admin user

Steps to reproduce:

1. Unzip http://download.forge.ow2.org/xwiki/xwiki-enterprise-jetty-hsqldb-6.2.6.zip
2. Delete the "data" folder
3. Start XWiki -> you get the DW
4. Click Continue
5. Select "No, this is a new install"
6. Click Install
7. Click Continue
8. At some point you'll get a pop-up asking you to login -> Click Yes and then enter these credentials: Admin/admin

After logging in you get an error: "You are not allowed to view this document or perform this action." and you are unable to finish installing the UI.

If you switch to the superadmin user you can complete the UI installation, but you get 2 merge conflicts.