I have Form Master 2008 2.0.5 running on DNN 5.03.01. The form results keep sending from the admin emails address, even when I set the Send From Action to User Defined with a different address, or Use Form Value with the submitters email address. The Send To Action and Reply To Email are both working correctly. How can this be fixed?

First you should upgrade to 2.0.8 from Snowcovered patahces and hotfixes. Them make sure the email addresses to be used are valid. If they are not if defaults to the Admin email address.