You caught us doing some quick maintenance, temporarily restricting your repository to read-only access.
Issue #185 resolved
In the $doInstall check on line 352 it is still using -eq 'CustomAccount' rather than -like 'CustomAccount*'
if( $PSCmdlet.ParameterSetName -eq 'CustomAccount' -and $serviceConfig.UserName -ne $identity.FullName )
So it will never update the service if -Credential is used