So I found out an odd behavior on this new desktop where I can only iterate the last 2 windows with Alt-Tab but not more than just the latest 2 windows. I cant go to a third or forth one. Anyone know what could be going on?

I went to the Shortcut menu and Saw Alt-Shift shortcut under change keyboard layout

On a second check I re-set the shortcuts and everything went well, not sure what happened but is working now.