Thanks for asking about System Integrity Control security modes with SpyShelter!
Pausing system changes can theoretically cause unexpected issues, so we decided to be conservative with this feature. However, for myself I do run this in “high” on two machines and I have yet to see an issue.
When we first launched SpyShelter 15 we found this “high” setting could cause an issue with some users in some circumstances, but since then we have made other changes to the software that should avoid any issues. Maybe we should consider making changes here considering the problem we worried about doesn’t seem to happen anymore.