In principle if the meat has lost about 35-40% of its weight it should be ready to slice. If you have uneven drying, you may want to wait a few more weeks. It is difficult to say if something is safe to eat or not without looking at it, smelling it, touching it etc.
Basically the entire UMAi Dry process takes place in a refrigerated environment which makes it safer.
The Coppa that is shown in the UMAi Dry video was also a little soft in the center and it was perfectly good eating.
Also, it is possible for small areas of white mold growth to appear on the surface, this same white mold often covers the entire surface of a traditionally aged Coppa.