Works amazingly well, thank you. Implementing it as we speak.
Two things to consider though:
1) Use SetDrawLevel(3) on the content window so that it will show up above the chat window (just found this out). Couldn't use my buttons when I parented the window and this was the cause.
2) Might want to add a tab tracker that saves the name of the created tab to a list then searches for that name to try to find the tab.index or something.
Right now if you change the position of the tab it will still associate the old tab.index with it. So moving tab 2 to tab 5, the new tab 2 will still open up the old tab 2's content.