I thought I would update how the 30-day visa went at Laksi:
PS: I was currently on a 30 day waiver and applied for an additional 30 days at Laksi.
I went to immigration at I.T. Square, Laksi (3rd Floor).
I was one day overstayed and it was completely fine.
It's just a standard procedure to pay the 500 baht penalty, and it was without any worry or slap on the wrist.
I asked my hotel to do a TM30 (which they did online) and they sent me a screenshot of it. I printed it out (and was completely fine).
There are a few photocopy and print shops in the same room as immigration.
I spent about 30 mins filling in forms and organising stuff, and then I had to wait about 2 hours to get seen, and then an additional 30 mins to receive the completed visa in my passport.
I arrived at about 2pm and left at about 5pm
I was customer number 255 of the day, and it went to almost 400 (last person).
I had a 1 hour massage while I was waiting (directly opposite the queue), one of the massage staff was checking the queue number (from time to time).
All in all, an easy afternoon.
Apparently, you can now book your appointment online, rather than queue and wait.
I have NO IDEA how it works. But thought i'd mention it.