What happened after the last crackdown in around 2014 is that it was strict for a couple of years and then it eventually became lax. It won't be lax anytime soon, particularly given the alleged Chinese criminal element to the rorting.
Which is what it's supposed to be - 8 hours minimum a week and legit schools typically run them over four days a week. If you don't want to turn up to class and actually learn, go and get a proper visa.
no recent history - you will be fine. Still don't know where you currently are but if you are still in Chiang Mai, there is an increasing number of options for flights. CNX flight schedule here:
The easiest way to get a new 45-day visa-exempt entry (you did not enter on a tourist visa, it was visa exempt) is to do a border bounce. If you're still in Chiang Mai, according to a post yesterday from
Presuming you haven't got a long history of being in and out of Thailand, fly to another country, spend a bit of time if you fancy and then come back and you'll get a new 45 visa-exempt entry.