Im not sure if this is known or not, but instead of downloading the ROM to your computer and transferring it to your Droid, you can download the ROM from your Droid. This way (assuming your rooted and have safe strap and any other necessary applications installed like safestrap) you can just wipe and go to Install from zip--> Internal SD card-->Download(not Downloads) and choose whatever ROM you have downloaded. It saves any ROMs you download also.
This is just a little shortcut for me and it is a little simpler in my mind than having to transfer files. (because I couldn't figure that all out really, Hahaha)