Thai font doesn't display correctly in preview

Thai and Lao System fonts doesn't show properly on preview when I type with vertical type tool. 
The font I'm using is Adobe Thai Font.
Screenshot from the latest beta version with "South Asian and Middle Eastern" Text Engine is on

When I hover Select the text

Same Thing with Tahoma Font. The issue has shown on the right figure. It still has this issue on version 15.2

When I type a word with Sara Um (สระอำ) It won't hover select properly as shown