What is your problem? I know the title of the thread states "shoulder subluxation", but why is it subluxing? Capsular laxity? Labral deformity? Was there a specific injury? Have you been properly evaluated?
Also, what is being done regarding the shoulder subluxation? Did you have any medical intervention (surgery, immobilization, etc)? I think that correcting the problem and reason for the subluxation should be your primary focus now. Also, I am assuming it is just one shoulder that is injured, so you have full range to do exercise with the uninjured shoulder.
Until we have a full understanding of your limitations regarding your shoulder, the best advice can't be given.