... that makes two of us 
And before you run into the issue... I already reported this, but you cannot get actual 1920 x 1080 frame size. Even if this is what is shows in the dialog, it doesn't come out that way. However, 1440 x 720 does. I got the "works to specifications" from R&D even though it doesn't actually work 
One option you might like is outputting the animation to images instead. You can make animated GIFs with PhotoScape. Sometimes this works well for short clips that you want to include in presentations. PhotoScape is free and allows you to make changes to the images in batch mode including image size "corrections". Just another tool in the toolbox 
Click on the image...
Animated GIF provides great control over looping when you mechanism animation stops in the same place it starts. You simply discard the very 1st image (since it is the same as the last) and you get a perfect loop.