I cant say Ive used a Bezzera before but can relate on my experience when moving from a single hole tip on the steam-wand to a 2-hole tip. Initially I found it difficult to get perfect micro-foam because the twin-hole was producing hot steam twice as fast and could not get the texture I wanted.
So one of the things I did was kept my empty milk-jug in the refrigerator so it remained chilled. This allowed me to prolong the milk steaming process and get a better result. I did this for awhile until I finally got use to the 2-hole tip.
Otherwise keep practicing with plain ol water ;)