Captivate 9 not displaying what's in the bottom of the capture frame

I'm in the middle of building Captivate 9 software sim eLearning modules, capturing software screens at 1280 x 720. Suddenly, the bottom 20-some pixels of the capture are not displaying. There's a white bar there instead. Here's an image of the lower left corner of a captured screen.

I can't figure out why this is happening. I haven't changed any settings, and there's no playbar. I double-checked my capture settings, and there's nothing different there.

Right before this started, I had done a few captures in which I moved the capture frame up about 20-some pixels so I could capture a little higher up on the software screen. I stopped and repositioned the capture frame to where it had been before. I can see everything I want in the capture frame, but the captured screens have that white area across the bottom.

I closed everything down and rebooted, and the problem is still there.

Does anyone have any idea what might be going on, and what I can do to fix it?

-Stuart