In your case, you may be able to skip right to step 5, so I'd try the htcdev stuff first. If you don't get an oem identifier key, you'll have to start from step 1.
1) You need http://www.mobfirmware.com/dl/behtas...%20dhd/rom.zip
Move it to where your adb files are.
Then do the following from adb:
2) adb reboot oem-78
>> this will put you in RUU download mode. I found you can run this command from CWM Recovery. Though... if you don't have any recovery I'm unsure how to hit RUU download mode. There is an .exe from HTC Dev that'll do it from Fastboot, so there must be a command (fastboot reboot oem-78
Once you're at the black screen w/ silver HTC logo, type:
3) fastboot flash zip rom.zip
>> This will change your hboot to one w/ an oem signature. Once it's successful, type:
4) fastboot reboot
5) Now, you'll need to go to htcdev.com/bootloader
and follow the instructions to get your KEY (fastboot oem get_identifier_token
) and paste it to HTCDev to get your boot unlock bin file emailed to you. Follow the last steps to unlock your bootloader.
The steps are something like: boot to fastboot> type oem command> copy / paste key to htcdev> receive email> download .bin file to adb folder> run command to unlock w/ .bin file (it's on the htcdev site).
NOW you can flash the custom recovery or boot imgs without getting the "Signature Verified Fail" Error.
Goodluck! I just went through this whole process of no CWM and no ROM so you can get your phone up and going w/ a custom rom from where you're stuck! Don't give up!