OK, Achieva is fixed!
Heres the story:
I went to Part Source first per Oldsmoboi's suggestion. As I was driving there (a 5 min trip from my home), the volt gauge was dropping. The ABS light turned on.
I got there with the needle in the danger zone.
Mike the service guy said that the machine to test the Alternator is currently broken, but I can test the battery.
Worried about not having enough juice to make it to the mechanic, I decided to just go.
Sure enough, the car wouldn't crank.
I got the battery out and we put it on the tester. It began charging (it read: charge 45 minutes).
10 minutes in, the charger gave up. battery was toast!
OK, so I bought a new battery ($100), and with fingers crossed, dropped it in and fired her up.
It worked, but the needle was still in the danger zone, and the charge light was still on.
Not wasting time, I thanked Mike (who was very friendly and helpfull), and booked it to the mechanics.
At the mechanic, they tested the alternator. Yep, it was not charging the battery.
Ordered a new one (reconditioned), and an hour later (and $300), it was in and the Achieva and all systems GO!
So, Im $400 dollars poorer, but everything is back to normal. The ABS light has not come on either!