Well, i'm not 100% sure what it is you're describing as the 'USB windows 7 installation driver error' can mean a number of things (i've ruled out USB 3 being one).
The next obvious one is that you need the AHCI driver to be manually added during install - so that Windows can the carry on the process.
When you get to the Windows 7 install screen and you see the partitions, drives etc.. Look for the 'Load Drivers' option and then select it. Be sure that you have the pen drive with the AHCI driver plugged in prior to boot up (or if that doesn't work add it when on that screen) - but don't boot from it.
Select the pen drive you have AHCI driver saved in and click on it, then they should install or follow prompts...
As much as i know from memory - been years since i did the above.
If that doesn't work - you're going to have to write a comprehensive description of the problem - as i'm having to second guess you to a degree - and if the above doesn't work i'm going to need a lot more input.