@mcriki-
You are placing the file into the correct location (root). The two things you need to do are:
1- Be sure the .bin file is fully uploaded and not still in cache (the information about this is found
where you originally read about this trick)
2- You need to restart your kindle while it is still attached to your computer via USB and NOT ejected. You do this by long pressing the power button until your kindle reboots.