You wrote:
> t::%OutputVar%
> %OutputVar%::t

Since remappings like a::b are activated before the script begins running,
you can't have a variable reference like %OutputVar% in them. To work
around this, you could use the Hotkey command to dynamically create a
remapping. The details of how to do this are on the remapping page:
http://www.autohotkey.com/docs/misc/Remap.htm

If you have further inquiries, please post them on the forum to get faster
response time: http://www.autohotkey.com/forum/

Thanks,
Chris