To lock a Task, Habit, or Smart 1:1
Right-click on the event associated with the Habit, Task, or Smart 1:1
Select Lock
Once locked, the event will mark itself as busy (if it's not already) and won't move if overbooked.
To unlock a Task, Habit, or Smart 1:1
Right-click on a locked Habit, Task, or Smart 1:1 event
Select Unlock
Once unlocked, the event will return control to Reclaim and will automatically reschedule if overbooked.