Hi,
Those files created in /root, are called core dumps. During your upgrade, something happened (this can occasionally happen when building from source), so the binary is either unable to find a library that it needs or needs an updated version library is required.
So, there are two approaches. If functionality is not being affected, a scheduled task to remove those core dumps. If it is, then really we need to find out why its doing that. The latter option would be ideal in the first instance.
Would I have remote access? These kind of issues tend to be very variable and really need someone to look into them.
Cheers,
Chris.