By default the root user that WAMP creates does not have a password set, however, POWER CMS will not except a blank password since this is not a common occurrence on live servers.
I found this video on youtube that walks through configuring the root password for your wamp server:
watch?v=sw6rd75sWR4
there is an issue using PowerCMS on security assist pages, see this post for details on fixing the problem:
showthread.php?t=15730