i.e. how do I e.g. link to another post from another thread... link to another thread... link to another web-page... link to an image. I.e. all the stuff that really makes up all this hyperlink/hyperthread stuff that "http" is supposed to be made up of...
I am somwhat blushing asking/proposing this, but would'nt it be a good idea to have a how-to written about how to use the forum software. (I have found the smilies though...) What makes this post even worse, is that I used to work in the programming business a decade ago and actually wrote some functioning elementary forum software. Time really flies by, doesn't it. )
E.g. I cannot find howto mark a post with a point in the "MvP" value. ... and there are many good advices in this forum. (The annoying thing is that I myself have gotten a couple of points, but I cannot find how to award other posts that are valuable that point.

You're right, the help for BBCode is obscured; look for the link on the right side of the edit window, below the Smilies. Click on BBCode is ON. See What is the little bar graph entitled: "MVP"? for an explanation of the MVP bar.