The rosettes are how it starts the flower stalk. It will eventually put out flower buds. If you cut it and plant it, it will still turn into flowers. The leaves from these stems can sometimes be propagated. Pups/offsets will usually emerge closer to the base of the plant.

IMHO, the most important factor in propagating from leaves is that your leave is removed cleanly from the stalk and has the primordial portion attached or you will grow nothing. This is the portion of the leave circled. The portion that remains on the stalk will, in some cases, produce new plants when or if you remove the head or active growth on top. Sometimes even new plants can be generated from leaves that are on a flower stalk. Again, it is important to remove the leave cleanly.

I agree with Alex, succulents only grow roots when the soil is dry. I don't think your issue is a very complicated one, just stop watering your leaves until after roots grow. In wet soil they will just wither and die. I just sit my leaves on potting soil in a nice warm area that gets some light and ignore them until they grow roots. Then I start misting them sparingly every other day until they sprout other plants. Goodluck, I wouldn't mind if you posted some images of your adult echeveria either :)

You're welcome. I have thephotos I posted on my blog in the Chip Budding post which may help you see the difference. If you remember the pith is nearly white, it may help when you see the juicier, brighter green cambium. You'll have to scroll down to see the photos. If you take some cane parts you don't care about and start dissecting them, you can quickly see the difference. Some roses have rather thin cambium. Others seem to have extremely thick cambium. That's one of the great benefits of Ralph Moore's Pink Clouds. Its cambium seems extremely thick, so it's very easy to graft on it successfully. With practice, you can easily remove the bark-skin and expose the layer you want. Quite often, particularly on green wood (either soft wood or green harder wood) cuttings, the skin is almost translucent, like a plastic or waxed paper. The green color you see is the juicy, green layer you want to expose. From experience, you don't need to differentiate between the extra layers represented in Seil's diagram above. Just think of it as three layers...skin, circulatory system and "bone". As long as you expose the circulatory system, you should have callus and eventually roots. If it turns tan and dries out, there was insufficient moisture. If it turns black and furry, there was too much moisture. It honestly can be that simple.