Hello.
I found this strange behavior of particles emitter when used flat shapes exported from 3dsMax.
I reproduced it in multiple Embergen versions (including latest 1.2.2).
Here is a simple plane which I export from 3dsMax. I tried all formats: fbx, abc and obj.
Then I import this object to Embergen and add a simple particle emitter and line upward force.
Here you can see how life or speed (hard to tell) affected by polygon ID of the mesh.
There is no vertex map, no masks enabled, setup is really simple and I can reproduce it using any mesh.
For example here is an array of spheres
The only way I could avoid it is to reduce Lifetime limits range to minimum so probably it’s Lifetime limits affected by polygon ID somehow.
If this is not a bug but a feature then I suppose it’s not very intuitive distribution of lifetime range.