Z90D7B: Reimage thin client with Windows 7 Enterprise

Hello,

I work for a non-profit, and we just received 25+ donated, thin clients.  PROD ID:  Z90D7B 60GSD/4GR - Part No. 909721-41L.  Model No.:  Zx0.  There have Windows 7 Enterprise installed on them.  I would like to reimage them so we can use them internally.  I created a USB image, using the USB Firmware tool (2.09?) and this file from the downloads page (BZB0_0858_8192.exe) which starts out fine when I push it, but then it fails.  

Can anyone provide and direct advice on how to image these units?  Please, and thank you.