Auto-Delete Isolated Environment feature was added into programs in ReHIPS 2.5.0. You may have noticed it. But why is it read-only and I can't check/uncheck it? Let's see.
Having this feature enabled will recreate isolated environment when program exits. It works like this. When a program exits, corresponding isolated environment is checked if it's free (no other isolated programs are running in it), then it's deleted and recreated from predefined rules (2 from this list https://forum.rehips.com/index.php?topic=9529.0 ). It means if RulesManager doesn't have rules for this program, it won't be able to recreate isolated environment for it. That's why the "Auto-Delete Isolated Environment" checkbox can only be modified from RulesManager, and Control Center has it read-only and only shows its state.