How did you read any of this thread as a flamewar? Sat asked you multiple valid questions which you've completely evaded twice now.
What limitation of $dll are you talking about specifically? How would integrating a MySQL API into mIRC overcome this limitation?
These are perfectly valid non-flame questions.
On a sidenote, all of those events can be implemented with the ON SIGNAL event as:
ON *:SIGNAL:MYSQL_OPEN:...
ON *:SIGNAL:MYSQL_CLOSE:...
ON *:SIGNAL:MYSQL_RESULT:...
Making the dll asynchronous as Sat pointed out would help with speed issues. I see no reason why mIRC would need to provide this natively. Seems perfectly capable of being scripted.