I'm the author of Rufus [1], and I was pleasantly surprised to see it referenced on the ReactOS Live USB creation wiki [2]. So first of all, thanks for that.
Now, considering that the documented method of creating a Live USB using Rufus can't exactly be qualified as very user-friendly, I have just added native support for the ReactOS bootcd/livecd ISOs in Rufus, so that you should just be able to point the app to one of those ISOs, and it will automatically create a complete bootable USB, with no need to download an invoke GRUB4DOS, 7-zip, etc.
What I would like to do, and about the only way I can see and test ReactOS, is to build from RosBE from FreeBSD or Linux, or Wine, and install onto a USB stick without having to make an intermediate boot/installation medium.
GPT-partitioned 3 TB hard drive seems to preclude installing ReactOS on hard drive.
There ought to be something like "make install DESTDIR=...".
This looks like it really ought to be on ros-dev?
Tom