I am not able top reproduce, on my test using the Simple Registration SP preset the forgot password link is added to the login page.
do you have other extensions installed? if so what versions?
If it is just a matter of the forgot password link, it is start forward to add that in using DW.
place your cursor where the link should go, type the link text:
Forgot Password
Select the link text, and use the property inspector to add the link.