I don't think instructions are necessary in our editor. There are categories on the left side. For example, if you want a fraction, expand "Math" and it's right there. It might take a little while to get used to what functions are under which categories, but once you find it simply "click" and put your values within the curly brackets '{}'.
Correct. I find it somewhat annoying as well, and I hope it's updated sometime (LaTeX tags added, for example). I do know the owners of ETO are on various other projects at the moment though, and that's a relatively low priority.
That's the site I used while our latex editor was still on the fritz. I copied and pasted the image though, not knowing ETO recognized the tags (or perhaps before it did?).