Kuru Kuru Kururin done in 6:06.33 (21980 frames) as stated in the Best Ending Normal rules on speedrun.com (complete all thirty main levels, save the birds).
Kuru Kuru Kururin done in 5:05.75 (18345 frames) as stated in the Any% Normal rules on speedrun.com (complete all thirty main levels, don't save birds).
The TAS starts at Power On with the GB intro.
Time with speedrun.com timing: 4:57.93 (17876 frames)
A new way to escape the starting zone in Ghost Castle 1.
The method given in Grasslands 3 (http://tasvideos.org/userfiles/info/52177347080337677) does actually not work here because of the springs on the bottom wall. So I wait for an additional 180° to give me time to adjust my position.
There are probably faster strategies, but this is a good start.