I added your listings to http://www.coreboot.org/Flashrom#Supported_mainboards and linked the board names to the matching product pages on your website. If you see any mistakes, please tell us.
By the way, if flashrom works for a particular board on 32bit Linux, it should work on 64bit as well and vice versa.
However, I believe the flash chip you mentioned for a few boards (PMC 49LF004T) does not exist according to PMC. Did you mean the PMC Pm49FL004T? I know what the official Tyan website says (PMC 49LF004T), but I believe that to be an error. It would be great if you could look up the actual engraved model number (below the colorful sticker) on such a flash chip.