Windows 10 Professional Version 1511 Available - Windows 10 (x64) English - What is the process for applying this ISO

Does this process require the use of the custom repository. When I look at the description of Fixlet ID 1100581, Windows 10 Professional Version 1511 Available - Windows 10 (x64) English - This Fixlet requires downloading the Windows 10 ISO image before deploying the Fixlet. You can use a custom repository to do so.Once this Fixlet completes, restart the target to complete the upgrade process. I think I have seen that you require MSDN account to get the ISO, is that correct?

However when I look at the action , I do not see the download url as shown below. What am I missing?

Is there a user guide that explains the process?

begin prefetch block add prefetch item name
=en_windows_10_multiple_editions_version_1511_updated_apr_2016_x64_dvd_8705583.iso
sha1=1b247b5b348e78c9bc3afd3c1cbe10cee3d1b9d5 size=4458960896 url={value of
setting “BESClientAllowCustomRepoDownloads” of client | “http://MANUAL_BES_CACHING_REQUIRED/”}en_windows_10_multiple_editions_version_1511_updated_apr_2016_x64_dvd_8705583.iso
sha256=c08d0636b52d56110367122b75428d6188c1c7aa7b0cc166172bbfe99c4c3661 end
prefetch block