<--snip--> > The problem with mouse-drag does not occur on the other disk.
<--snip--> > Of note is that when I start /usr/games/sol as root the problem
> disappars---I can drag cards just fine.
This implies that your issue is 'user' based.
One of the re-occurring issues with (GUI) applications after an update can be traced to the 'user's personal configuration files for the previous application version.
It runs as 'root' but not as 'user'-> it is either a permission issue or a 'user' configuration issue.
Two steps you could try...
Create a new 'user' and login. See if the app runs as non-root (no prior use of the application - no stale personal configuration files, rules out a permissions issue).
For the user that cannot run the app, purge all personal configuration files for the application, these can be tricky to find.
Your desktop will determine where they are placed..
E.g.
.kde
.trinity
.config
.cache
A good punt is to purge all of '.cache' and then strip out anything in '.config' (if it exists, or look elsewhere).