https://www.youtube.com/watch?v=ngElkyQ6Rhs
If you look at that quick shot at 1:09 where Boyega and Ridley are running rapidly towards the camera, with BB-8 in tow, it seems that there is definitely some CG going on with BB at this speed. I could be wrong but that's how it looks to me. Either way, I think that's a totally legitimate use of CGI. I'm so impressed by the prop, and if it takes a bit of CGI here and there for certain shots to make it happen, at least you can bet that the effects will be top notch.
If you look at that quick shot at 1:09 where Boyega and Ridley are running rapidly towards the camera, with BB-8 in tow, it seems that there is definitely some CG going on with BB at this speed. I could be wrong but that's how it looks to me. Either way, I think that's a totally legitimate use of CGI. I'm so impressed by the prop, and if it takes a bit of CGI here and there for certain shots to make it happen, at least you can bet that the effects will be top notch.