do you have any idea what she was getting before you moved her? 2 lbs of feed is not enough to meet vitamin mineral requirements when feeding ultium. I agree with being on a high fat feed for a horse who needs to gain weight, but you will need a min of 5 lbs per day to get what is on the tag. Since her teeth were so bad it may take a while for her to be comfortable eating so it may take more time than you would like. Hay is the most important thing, so free choice is best, but id try to keep track of how much she is actually eating. And if in the next 30 days or so of doing what you are doing she does not start to gain weight, i would start to increase the feed.
A ration balancer feed like enrich 30 is only to be used when you have an easy keeper horse who requires less than 5 lbs per day. So if she maintains good weight on less than 5 lbs per day that would be a good choice to add at about 1 lb per day, but she sounds like she will end up being a harder keeper and need more than 5 lbs to get to the weight she needs to be and stay there.
I am an equine nutrition specialist, so if you would like to PM me and talk more specifically please feel free.
I, too, am an equine nutrition specialist, and have been seeing FANTASTIC results using a ration balancer feed like Enriched 32 for HARD KEEPERS, when used WITH another source of calories such as Wellsolve.
MOST of your run of the mill lines of feeds are made with "Ration Balancers" as their backbone-when a label says you have to feed a minimum 5 pounds, that's like saying there's "one pound of ration balancer in that 5 pounds".
When you feed a balancer on top of something like senior, high fat/low starch, etc., you're giving a super boost of their core requirements ON TOP of adding calories from those other feeds.
A horse that is needing to gain weight, IMO, is in "heavy work."
So, a typically feed label will say it needs 8 pounds of feed or MORE per day. (Not including hay).
By separating the balancer from the calorie source, a person has the ability to increase or decrease either one:
An easy keeper in maintenance: 1 pound per day of RB.
An easy keeper in work: 1 pound per day of RB plus 1-2 pound per day of calorie source...
Compared to an easy keeper in work requiring 8 pounds per day.
I've seen many horses be given however many pounds the label says withOUT successful weight gain.
Those same horses, when given a proper balancer on top of the calorie source feed start to BLOSSOM after as few as 2 weeks.