Thanks Robert for quick followup.
Great news for Thai support potential.
Regarding the dictionary, I believe there are a few free Eng-Eng ones, e.g. Webster 1913, Worldnet. Calling up dictionary during reading by pressing some button, use other buttons to choose any word within the page, press another button to confirm lookup; then showing a popup small box displaying the definition. I like most the way Pocketbook 301+ or 360 implements on dictionary lookup, very convenient and intuitive.
Your engineer should search the video demo in Youtube (keyword Pocketbook 301 or 360); or see my thread here:
https://www.mobileread.com/forums/showthread.php?t=58606