Tetrabenazine might help. As soon as it is available in the U.S. you can talk to the doctor about whether it would be right for you to try it. If you do so, start slow and move up with the dosage. You should also be on an antidepressant before talking TBZ because it can cause depression.
As for stem cells, we are years away from a treatment based on them. Researchers have had good results in the HD mice by using BDNF and something called Noggin to stimulate the growth of the mouse's own stem cells in the brain into becoming medium spiny neurons, the type which are damaged by HD. There needs to be a lot more work before this treatment can be safely tried in human beings though. I believe that the importance of the stem cell research is help in recovery once researchers are able to safely and effectively turn off the HD gene.
I am so sorry I overlooked your earlier question!