As described in my previous post ...
1. I went to my local TRD-office
2. I explained that my overseas-bank wanted to send them year-end information, about my offshore-banking
3. That I therefore needed to give them a Thai T.I.N., to identify me to the TRD
4. I showed them a bank-statement from my bank, which had my Thai-address on it
5. I confirmed that I did not, and had never, worked here in Thailand ... and lived in a house owned by my (Thai) wife, but that I didn't have her house-papers (and anyway don't appear on them)
6. I told them I had been living here for 20-years, they could see my visa/extension-status from my passport
7. I said I had two Thai-bank accounts, with KBank, knowing that the miniscule interest is reported to the TRD
8. The officer spoke with her superior, and made a brief phone-call
9. She took a couple of photocopies, and issued me with a T.I.N., which I signed a register for
At no point did either of us mention Annual Tax-Returns.
I generally played-dumb, and stupid (this comes naturally), but appeared wishing to conform to the new-requirements and to my bank's CRS-needs. It took less than two-hours.
That's it, basically ... do you have any specific concerns, about your own case ?