When there is a program version conflict in one of the data files, the program displays a message allowing the program to be interrupted, or to continue its running.
For changes in versions of the data files (for example, when new features are added), it is probably better to stop the program and try to update the data files.
For changes in the program versions (mc-set version number), which occur frequently, it is probably safe to ignore them and continue running the simulation.
In both cases, once the data file is updated in the new version of the program, the version numbers recorded in the data file will be updated and the error message will disappear in subsequent running.
