George, I am German and I would like to apply for a DTV softpower studying Thai language. Please, tell me which school in Thailand (which city) did you enroll in?
Apply for an International Driving Licence at home. Officially it is valid in Thailand for 3 months. If you stay longer you'd better check for a Thai Driving Licence. Immigration....Medical Certificate and some small tests at the Department for Land and Transport (DLT).
Sorry, but I've never been there. But if there is an official border crossing, why not! Wherever you cross the border it all depends on the officer of the immigration.