Scenario:   I followed the maspawngroup guide on the plugin page to set up a locked crate on top of launch site and inside mil tunnels.  It seems to run on a 30 minute timer to check if it needs to respawn and it does if it is missing. Most players have figured out if you camp for 10 minutes, there is a good chance they will get a 2nd locked crate for free.  Is there any way to make this respawn timer reset to the full timer once it has been looted and despawns?  Thank you!

Yes, that sounds reasonable. I'll put this in the issue tracker. Planning to work on this plugin in March.

I just released v0.14.0 which adds new options for this use case.

• (Spawn group option) PauseScheduleWhileFull: true/false -- While true, the next spawn will not be scheduled until the spawn group is below its max population. For instance, if the spawn group is at 2/2 population, and respawn delay is set to 30 minutes, once the population reaches 1/2, the 30 minute respawn timer will be started. In vanilla Rust, this feature does not exist, meaning the timer is always going, allowing for situations where loot spawns shortly after loot is taken.
  
  • Usage: maspawngroup set PauseScheduleWhileFull true while aiming at the spawn point
• (Spawn point option)PlayerDetectionRadius: number -- This number determines how far away players must be, in order for this spawn point to spawn an entity. By default, vanilla behavior checks within 2 meters for normal spawn points, or RandomRadius plus 1 meter for radial spawn points. Setting this value to greater than 0 will override the vanilla behavior, allowing you to enlarge or shrink the detection radius. While a player is detected within the radius, the spawn point is considered unavailable, so another spawn point within the same spawn group may be selected for spawning an entity.
  • Usage: maspawnpoint set PlayerDetectionRadius 30 while aiming at the spawn point