I have created a Google Earth KMZ file with accurate rings and track plots at 20 kt intervals from 490kts to 410 kts and projected where 390 and 370 kts would fall on the 00:11 ring. ( I didn't include the 00:19 ring because I felt it would add more clutter than information.)
I chose a different route than mm43, I plotted what is probably the shortest route possible; I made the route through the strait pass south of MEKAR and from the 18:28 ring the route went direct to IGEBO and POVUS.
I included stuff from east of the 18:28 line, but the purpose of making this kml file available is for the 19:28 line and the southern route.
The KMZ file is at:
https://www.dropbox.com/s/jz4d1j674o8g2a3/MH370.kmz
Pictures of the Google Earth presentation are at:
http://i1349.photobucket.com/albums/...psa1a0ba64.jpg
http://i1349.photobucket.com/albums/...ps31397ae3.jpg