1. to use that black and red thing yes, there is supposed to be a short metal shaft that connects the two. I don't see any real reason to use one though. Instead just screw the shutter release cable into the shutter itself. Because the red and black thing is in the way, you can loosen the retaining ring and rotate the lens, or you can just replace the lensboard with one that doesn't have that thingy (if you do try to find a shaft, note that you will also need a special tiny thing that screws onto the end of your cable release because the cable release wont screw into the red and black thing. its supposed ot be a quick release--pull the red thing down and the release comes out without unscrewing--but they are more trouble than they are worth.)
2. the front and rear lens assembly unscrew from the shutter. Usually it unscrews easily, but sometime the threads are frozen and difficult to get started. If you remove a lens assembly be careful because in some cases there will be shims that space it out. You'll want to put them back in place to maintain the spacing.
3. Cock the shutter then press down the little rectangle with a wing on it (the last item clockwise in photo 3.) That will oven the shutter for focusing. To then close the shutter, press the release. You'll have to recock before firing.
EDIT: Assuming the shutter is a copal #0, something like this will be easier and cheaper than trying to find a matching shaft:
Also, if you're using a Linhof Technika, you probably want a board that has an offset hole--the one you have looks like it does, but I'm not certain. If you have most other cameras that work with Linhof boards (including some other Linhof cameras) you're better off with a centered hole. The link above is a centered hole, you can also find offset hole boards for a similar price. (the hole is lower which places the lens at a lowered position because Technicas have front rise but no fall. The offset board builds in a little bit of built in fall so you have to raise the front standard to center the lens, but you get the capability of going back down if needed. With a centered board on a Technica, you get no fall without resorting to indirect fall.