It's a Trap 5E for revealing monsters??

Is using the Trap for 5E to reveal monsters too much work for little payoff?  If I have 3 bad guys hiding and the DC to spot them is 18, when the players come within 20' I want them to roll their perception to see if they notice the bad guys.  If they roll less than 18 then the bad guys don't show up until they get within 10', at which point bad guys pop into view and attack them.  Otherwise the bad guys pop into view when the players make the spot DC of 18. Should I even be using the Trap for this?  Or should I just roll Group Check Perception and then select all tokens and move from GM to token layer? What do you guys do?  Is there any value in this?

Sounds like a good setup for their passive chance to be detected.

That's a good idea... never thought about using it's a trap for mobs!

Maybe use the path trigger for the 10 foot ambush point?

Well, my traps NEVER trigger when somebody walks near them so it's not that awesome yet.  maybe I have a setting wrong still. What is the path trigger?  I see it as an option, but don't understand it at all.

Draw a line and select it and your mob... then run the wizard. It acts like a tripwire for the trap

Default settings for the trap is that it triggers when they enter the traps space 

Very cool, so I can have it trigger a ways away without setting the trap radius to 40' right?  I like that.  I'm going to try it for my ambush settings outdoors.  (I LOVE long range encounters with difficult terrain.  I love it when the PCs go, "what, he's shooting us from 400' away?  What do we do now?"  Plus it let's the awesome archers shine)

Currently, the 5E trap theme only supports passive perception.  The Pathfinder trap theme supports active perception in a way. Characters with the Trap Finder ability get an automated active search roll if they come within 10' of a trap. Something similar could be implemented for the 5E trap theme that doesn't require any special class ability. It would just automate an active check for a character who comes within a specified distance from the trap, as configured with a new field in the trap creation wizard.

That would be cool Stephen.  If it's not super difficult I think it would make the trap mechanism even more useful as in rpgs there seem to be a lot of potential ambush situations.  I really like the fact that your script is SOOOO user friendly.  I like them to be idiot proof.

Thanks! I really try to make my scripts as easy as possible to use for everyone.