I figured I might get a quicker response if I made a new thread. If you read this thread here Brick
I have the same exact issue.. I started out doing the same exact thing. I wanted to unroot my phone, so I used SBF to root and to unroot and followed the instructions for # 5.. but I've never been able to get the RSD Lite to work for me.. I connect my phone.. press up on the D pad and power.. it detects my phone.. I can select the file that I want to install but I'm never able to select "start".. so I've always used the SPrecovery.. however when I press x and start.. I just get the triangle with the exclamation mark.. I can plug in my phone and mount the sd card.. but without SPRecovery I dunno what to do.. I ultimately just want my phone unrooted.. I don't really know what to do from here.. any help?