At least one of the problems appears - notice the word used - to be solved. I actually checked into Twitter just now and it accepted the old/new/old... password.
I came accross the complaint form and informed them of the situation. In the complaint I mentioned both problems and wondering if I should tell them the sign-in is solved. Perhaps not since it could go awry like the follower count at any moment. At least making an official complaint will (one hopes) result in receiving a ticket, which in turn means they'll look into it. Eventually.
So now all that remains is the follower count situation. I follow you...you follow me...we all follow each other. I should only be so lucky!
FOLLOW UP: I tried logging in just now and it worked again! Could fixing the follower count be far behind?