Here's a tip, don't enter all 16 digits at once. Enter the customary 5 digits first and enter. Then it will prompot you again with a screen askiing for the dividend award coupon code. NOW enter all 16 digits and $$$ in your pocket.
Good luck, works for me.
Oh, with the $100 coupon, seems to be no go for stacking on the $30 or other promotion code like adding a backpack, etc.