The CRO and DVC reservation systems do not "talk" to each other. At a minimum, you have to go to the front desk and check out and back in again between the points and cash portions of your stay. You get new room keys.
The resorts do try to keep you in the same room, but sometimes it just doesn't work out that way. I have not heard of anyone having to actually move for some time so the resorts are doing a good job keeping people in the same room when they can.
I assume you are talking about the AKV for your example, because it is my understanding that the standard view rooms at the BWV are not available for cash reservations. Neither are the boardwalk view rooms. There are also other categories that are not available for cash. The dedicated 2 bedroom units with 2 actual queen beds in the second bedroom at the BCV are another example.