My apologies if this posts twice.
Danish, thanks for the reply. I couldn't quickly locate the files you mentioned, but I downloaded the two redistributables from Microsoft; your posting the exact names required made it very easy. Both redistributables installed without incident; I just had to agree to the license agreement, allow the program to make changes, and a few minutes later it indicated successful installation.
It makes me wonder why the CCS install could not do the same thing.
When I restarted the CCS install, all was successful. I noted in passing that one of the first things it did was to instal the 2005 redistributable (so that's 2005, 2008, and 2012 it needs). This seemed to work without issue, making it all the stranger (to me at least) why the two later redistributables didn't install.
So all is well now. Thanks again.