I'm not sure what is going on in your shots. Looks like you have either (a) some 4+ polys, (b), not all the polys are set to sub-D, or (c) one or more points at the corner need some weight map yet.
Adding detail to a curved surface is tricky. Take a look at one of Lewis' wireframes if you want to see some great detailing (
http://vbulletin.newtek.com/showthre...threadid=11267).
Below I just grabded some polys off a disc object, 3 segments, and using smooth shift, right click, and drag built the window. Then I did a few bandsaw cuts to square out the opening. On a few of the vertical segments added by the bandsawing there was a crease so I welded a couple points to get rid of it (you can see the triangles at the corners where I did the welds). There is a very small crease in the corners that maight look bad if doing any close-ups. I think I did this by right-clicking too many times. On the left corners I added some weight mapping to see if that would help. You can see the difference in the wireframe.