That sounds really cool. This kid is looking excellent, for an event what about a freight train derailment in the forest, few injured and a leak of chemical gas
One hell of a derailment, considering there's almost no railway on the map
Though accident(s) involving chemical transportation truck(s) is a good idea...
As for the fire breaks - I won't promise anything, as I am not sure if I'll be able to deliver. I'm not sure my scripting skills will be enough for such a job.
Also a little problem with fire breaks - it is close to impossible to create forests in Em4 with "tree" objects, as the game uses a special, non-chainsawable (non-physical) "forest" model which is a collection of about half a dozen trees and some undergrowth. The performance drops very significantly if single trees are used.
Custom events unfortunately require mission script logic which is very very very hard to do. Believe me.
The most one can do is use the default Em4 events and position them in a way that the forest complicates them and makes them more difficult to solve. An example would be a gas explosion in a cabin surrounded by trees. Now that would be a challenge.
I believe HAZMAT accidents may be recreated based on MVA accidents with a little help of mission-used objects, like that truck, which spills chemicals upon destruction.
Oh, and good luck responding to a "person fallen" call, if that person is hiker in the woods, without assembling a full-fledged Search and Rescue team