Go to the frame you'd like to increase it to, and click drag down to the bottom so you've highlighted all areas, then hit F5 which will increase your frame range to where you placed your selection.
Thank you. I know it was something simple but trying to find it was IMPOSSIBLE!
Haha, yeah a lot is hidden there in Flash. Also, just for the heck of it, if you select a frame range and want to DELETE those frames, you hit SHIFT F5!