Sorry, I didn't see this until now.
When the power went out, it must have been out for several hrs. it no longer had negative ink pressure, and released into the drain pan and down into the waste tank. (Don't try to re-use it from the waste tank. That's where you will find all of your ink now. To avoid this, you can purchase a good PC/surge protector with a battery backup that will last a few hrs.
You will need to call the M&R digital dept in the am before doing anything with loading the ink. If it ran out completely, and is giving you that 2nd warning, there is a specific procedure you need to do. It's simple and quick but needs to be done before just adding ink and starting up.
There are two types of ink warnings.
1st, is the warning you see every time it prints. "Grey in low" This is a non issue warning, simply stating that ink has been used, (wait till it goes away) before operating again. There is currently some ink in the tank, but basically it's saying "I'm filling the reservoir holding tank" back up, so don't use me until I go away on my own. Don't click OK when you see this simply because that is a manual over ride and stops the filling process. It likes to be full at all times to be prepared for a full and complete coverage for imaging. If you see this only, when you power up, all you might need to do is just re-start everything on the machine and power back up correctly. You will hear a series of clicking, filling up the tank.
The 2nd warning, indicates that the reservoir holding tank has been completely emptied. Here is where it gets tricky and the procedure must be followed well. Again, it's short and easy (if the black ink pump) has not also been emptied. Call the M&R tech and they will walk you though it. Don't call Greg directly, because if he's at a customers, he is dedicated to that customer at that particular time and usually won't answer that call until he's done or on a lunch...and he most times, does not take a lunch. So call the Digital Dept first.
If the pump has been emptied, it's still recoverable, but is a further process. "takes about 45 min to complete. You will have to draw ink back out from the back "main tank" where you put ink in, (into the pump) to prime it. Then, you will go through the 3-10 min process of filling the reservoir holding tank.
Sounds like a lot, but it's pretty quick if all goes well.