I figured it out. Actually, we figured it out. I should have taken a wider angle screen shot the first time so that my layers were showing. For anyone who is having this problem in the future, here's where I went wrong:
When I first had trouble figuring out how to continue a bezier line I started to randomly create masks to troubleshoot the issue. At some point I accidently moved my main mask (Empire State building) below my image of New York. When a mask is 'closed' the lines are highlighted in thick red, BUT if the mask layer is below the main image then the lines appear very thin. This is how Motion indicates to you that you have control over a mask layer that is under the main image.
Important takeaways:
- Take whole-screen screenshots so people helping can see your mistakes
- To continue an uncompleted bezier mask, toggle on 'edit points' in the menu bar below the viewer (shortcut: Tab), Option + Click the last control point and continue the mask until reaching the original control point to close the mask (holding down Option the whole time). Using this continuation method will make the cursor an 'arrow' and not the bezier 'pen,' but still works the same
- A mask layer that is placed under the main image will show thin red lines instead of thick red lines so that you can identify which mask layers are above the image and which are below (to help you!)
Thank you rowie302 for constantly checking back to this thread! I totally gave up and then you replied again and I stopped Netflix and kept trying. I have masked many things before which is why I got so frustrated with this. It seems that a misplaced layer or a one degree discrepency in Z-space is always where I go wrong in Motion.