Already I contacted them. They have no module blesta have for other systems which I also tested.
As to buy the domain with the hosting, I have not found that option in blesta.
However, without the module Openprovider I can not work, it is my domain provider.
I will test the system in a few months have if you are improving and are encouraged to put more modules domain providers.
PD: Forgiving translation, use google translator.