How do a get my program to start up automatically when TINI is rebooted?
The /etc/.startup file contains instructions to slush which are read at boot time. You can add an entry to .startup which launches your program. See the FAQ at http://www.jguru.com/jguru/faq/view.jsp?EID=22329 for additional details.
If you don't need to run slush, then you can convert your application to hex and load it into bank 7 in place of slush. Then it will be executed upon boot.