For bike ownership, you need only your passport and certificate of residency. But.... at MTT in Bkk you can't get CoR until you've been in the Kingdom at least 90 days and done your first report in person. For license, an IDP is fine, infact your local license is often also ok.
I drove to pattaya from bkk on Sunday and returned yesterday. There were no roadblocks, no check points and no military. Traffic was normal. But, the motorway closes between 9pm and 4am.
You'll need 2 certificates of residence if you intend to get a car and bike license. 200baht each. License department at DLT is closed. Might reopen 1 June.