I need to split about 600 pages using Pages –> Split Pages, some of the pages have 4 splits on them. Is there a way to add that button to the tool bar or create a short cut to it?

You can use

Settings | User settings | Hotkeys tab
Pages –> Split Pages
Change …
Choose Hotkey
Ok
Ok  

Until now I couldn’t figure out how to actually change the
hotkey – I was trying to type in the box and it would not allow that.

You need to press necessary keys on keyboard.
For example, press Ctrl and S at the same time to add this combination.

Available programs:

• Advanced TIFF Editor Plus (free download, home page);
• Advanced TIFF Editor (free download, home page);