This is a new installation of SKUID and am working with the out-of-the-box CRM Examples, i.e. Opportunity Tab view, but it only looks for owners on an Opportunity. We use Opportunity Teams, looking for suggestions how best to add new Filter Button (Show My Opp Team Records).

From what I’ve put together, I added a second model for Opportunity Team, then tried to have it drive the Opportunity Id, no luck.

You are on the right track. 
1. Add opportunity team model - with condition so that only records where the current running user are returned.  This model should be first in your list. (or above your opportunity model)

2. Change the opportunity model’s condition so that it only includes Opporotunities that are found in the Opp Team model. 

There are problems with this approach if users are typically assigned to hundreds of opps.  In this case, I’d reccomend using the Opp Team table as your primary display, and include parent data from the opportunity in the model and table for additional context.  You can add the opportunity model in a drawer (or popup) if you need editability of the Opp Data. 

One of these two strategies should get you started.