I'm pretty sure all these Asian 'grass' events are synthetic - only tournaments in the US (Newport), Aus (25k/smaller challenger events) and obviously GB are actual grass.
Is there a rule about which rankings list should be used for deciding the seeds?
The main draw seems to have been made today after this weeks rankings were out, as I saw them on the WTA website last night, and yet they have used last weeks rankings otherwise Naomi would be the number 1 seed.