These steps are adapted from http://tech.surveypoint.com/posts/tomato-firmware-install-on-asus-rt-n10p-router/. I had simplified the procedure for you here.
- Download the appropriate tomato firmwire. I used tomato-K26-1.28.RT-N5x-MIPSR2-121-Max.trx. You can download it from http://tomato.groov.pl/download/K26RT-N/build5x-121-EN/. Newer version (latest is v124) are available in http://tomato.groov.pl/download/K26RT-N/ .
- Download and install asus firmware recovery program from http://support.asus.com/download.aspx?SLanguage=en&p=11&m=RT-N10P&hashedid=wU7ZgKmZf29DK6D0
- Start the firmware recovery program.
- Select the firmware (do not press upload yet)
- Unplug the power from the router (no need to use static IP in your computer).
- Holding down on the reset button, plug in the power to the router.
- holding the reset button till the power light blink slowly,
- Press the upload button in the recovery program. 100% upload will be completed in a minute.
- Wait for 30 minutes more without disturbing the router. You'll probably see the errors in the firmware restore window. Do not worry about that as long as wait for 30 min.
- Connect to 192.168.1.1 in your web browser.
- Switch off the router, press wps button and turn on the router --> to reset the nvram.
- Configure the router and have fun.
