This is easy, I did about 25 islands yesterday evening
I do it this way:
1. draw a generous hydro polygon, make it transparent
2. draw a plain polygon of the outlines of the island, leave it opaque.
3. draw a simple exlude hydro polygon around it, adjust the transparency so you see your island again. Stay inside the hydro poly from step 1 with it.
4. mark the opaque plain island ploygon (the whole thing, not a vertex!) with "set as hole" and (in polygon drawing mode!!!) and assign it to the hydro poly in step 1. Be sure to get the right one in a complex setup. Now, if you work with satellite-backgrounds, you should see the background from the sat-image through the "hole". Then you did it right. In FSX you will see whatever landclass is defined for that patch of land showing through the hole. Remember, there is always land under the water polys. Of course you also can set another landclass poly with the exact circumference of the hole on the island, or rework the landclass underneath with the LC-tool, etc etc.
5. draw shorelines, make elevations, etc
If you re-create a default island that has already been there you might have to exclude the old shorelines or other terrain features first.
And just in case you want to create several small islets near each other, you can set them all on one hydro poly, Theres no need to define one for each islet.
@ Joe, I think the clockwise drawing only refers to the shorelines and the direction of the waves on them. Clockwise drawing = land in the middle, waves from the circumference. If you draw it in the wrong direction, no prob, the effect can be reversed in SbuilderX without deleting and drawing the shoreline again.
HTH
Mark