Ita crazy how fluid the process is. They have to be the worst government department to deal with. Improvised chaos.
So I muddled my way through it. As of yesterday the RENEWAL process is:
Come before 8am, earlier the better as there is a loose queue system of sorts. Sit/stand under the tent for renewals only. At 8am a lady comes around and gives everyone a Thai form with a queue number written on it. This is for their use only. This is limited to 100 a day, so be prepared to hustle if you see you're going to miss out. Yesterday there were more than 100 trying. Seems sitting is best as she gives queue numbers to those sitting first and regards that as the start of the queue.
All 100 are then taken upstairs where 2 queues are formed, one for Thais, one for foreigners and your docs are checked and kept. Passport, old DL, medical certificate, residence certificate, copies of passport and visa page. You show them your e-learning completion receipt also at this point. This was done in about an hour for all.
You're told to come back at 1pm sharp and hang around counter 5, where a guy calls you up one by one in queue order it seems for the reaction test (pedals) and the obligatory red green yellow test.
Take docs and pay for licence with new queue number the guy gave you. Take docs, keep passport and put in the camera ladies basket and wait for her to call you up for a photo and driving licence to be made.
Hope this helps someone.