Truck Bus Fans?

It has been in the paper recently that the Thai Transport Minister wants to push through with the 4,000 cng bus lease program.

Bangkok is where I first became aquainted with natural gas vehicles a few years back. Subsequently I became an investor in a Canadian company (Westport Innovations) which has a joint venture with Cummins (Cummins Westport or CWI) and they manufacture natural gas truck and bus engines. I did read in a Thai blog a few months ago before the program was nixed and brought back to life, that CWI was a favored provider of the engines.

Looking around Bangkok, I see a lot of new Golden Dragons and a couple of Sunlong (a division of Xiamen Golden Dragon) which I believe has a manufacturing plant in Chon Buri. There should also be some Hengtongs and Donfengs around, but I haven't been able to ID any. These Chinese bus manufacturers do offer a CWI engine but what is actually under the hood I don't know. I am not trying to pump a stock that has me losing my ass off, I am simply fishing for local knowledge. It's sort of a hobby of mine researching the world of NGV's. Specific questions would be.

Has anyone ever seen an actual CWI engine in Thailand?

Who manufactures the new CNG yellow buses with the name City Bus on front?

Has anyone seen any Dongfengs, Hengtongs or Fotons?

Are there any good NGV forums in Thai ?

As for heavy duty CNG trucks, I have only seen Isuzu, Mitsubihi and Hino which I suspect are conversion jobs.

Any input on the truck and bus world in Thailand would be appreciated. Thanks