Go back to the root
http://soniccenter.orgLog in at the top if it doesn't carry over from the forum
On the left side, look for the Submissions button and click it
Choose "Sonic Rush" from the drop down menu and check the Times and Time Attack boxes
Fill them in and click Submit
Confirm them at the next screen (if you wish to include comments about certain levels, you do so at this screen)
Wait up to 5 minutes and they'll be entered!