yes, so far everyone doing it only enrolls 6 months course and able to get the 5yr visa. Not sure if they will ask for extensions or northeastern in the future, but should be ok for 5yrs time at least. Lots of people doing it and successful, see DTV group of interested in entire process.
Your address from your home country is needed on the application. If your living in thailand and leaving to get this visa - so you will spend a few nights in cambodia or laos - you will also need your reservation of hotel. But your permanent address and the proof they need on bank statement or utility bills is for your primary residence in your country.
You must move it all into one account. The account has to have been open 6 months, but the last balance statement must show 500,000 baht. Can't use multiple accounts.