WPF Animation Help

I'm attempting to move my storyboards out of my code and into the markup. I'm running into a little trouble and I'm not sure how to go about this. I have 2 doubleanimations in 1 storyboard. The 2nd doubleanimation isn't suppose to start for a given number of seconds. The delay is set by the user. I need to add the begintime to the 2nd animation at run time. The delay value is stored in the settings for the application. Is there a way to do this in the markup or does it have to be done in the code behind and how?

Thanks