I frequently use Skim to read scientific working papers in which tables and graphs don't appear in the body of the paper but are all relegated to the appendix. Split PDF mode is thus a very convenient feature for me. Alas, I would often like to annotate stuff in the tables in the appendix but as far as I can see Skim won't let me add annotations in the bottom frame of the split screen. The only way to add them is for me to scroll down to where I want to make the annotation in the top frame and then scroll back up when I'm done to continue reading. Is there any way to make annotations in this bottom frame and if not, could this be added as a feature?