Doubt it. My guess would be either in English, in Thai, or in the local language of the country the Thai consulate is in. It is not like with the LTR visa, where a central agency in Thailand (the BOI) pre-approves everything and needs translations. But that is also why I assume that the DTV might only be available at consulates in ones country of residence, and maybe not at 3rd countries.
You are correct. A common thing people used to do with the METV (Multiple Entry Tourist Visa), to leave and re-enter a day or so before its expiry date to obtain another full period. Should work with the DTV just the same, effectively giving 5 years + 180 days.
Why shocked. This is how a multiple entry visa works. Shocked in a good way, right? Technically, in the last year, you should also be able to extend once even if period is beyond your visa validity then. And extensions are optional: you could also just bounce in and out every 180days to avoid extension fees.