I have 3 different firmnesses of therapeutic putty, i've been using the softest one on my right hand, and i'm not supposed to use any on my left hand quite yet... actually if my therapist knew i was playing the bass, she would probably tell me not to...
Glad to hear the first part is over and no compications occured.
On the bass playing, i would ask you to consider telling you doctors about it, it is a factor that need to be worked into your treatments.
Remember your treatments are controlled so you make the best use of what you have, what you develop, and what you need to develop.
If you are trying to get back to an normal everyday hand use this will be reflected in the treatment, but you are not, you as a musician are developing a "higher" use for the hand, and this needs to be factored into your doctors treatment.
In my case it was always understood what i was working towards and some the ideas i came up with (including the board) were developed for specific purposes, after talking about my needs to develop my hands for playing again, not just everyday life.