Your experience sounds a little different than mine, but then again I didn't follow the instructions in the link exactly.
First I downloaded the PC10IMG.zip file to my sdcard, making sure it wasn't in another folder. Then I turned off my phone, then turned it back on, holding volume down + power until the bootloader opened. at that point it found the .zip, installed, and then proceeded to reboot and hang on the second reboot. At this point, I removed battery, took out microsd, put it into a microsd reader on a computer, you can delete it or rename it as i did, in case I want it later, named it "DZPC10IMG.zip" ejected the microsd, put it back in the g2, turned on. From there I forgot exactly what happened, I think it goes back to recovery perhaps, if not then turn off again, use volume + power to boot into bootloader, choose recovery, depending on the image i believe it installs CWM for you, from there I wiped everything again, then installed new ROM.
Personally, I've used that ROM and while it was awesome, I'm using Virtuous Affinity now cause I think it runs a little easier, and it's also Sense 3.5. It ran a lot better once I activated swap and supercharger. Let me know if you want help getting those going