The mod Schall Endgame Evolution caused a non-recoverable error.
Please report this error to the mod author.

Error while running event SchallEndgameEvolution::on_gui_click (ID 1)
SchallEndgameEvolution/control.lua:198: attempt to index local 'unittable' (a nil value)
stack traceback:
SchallEndgameEvolution/control.lua:198: in function 'update_gui_evo'
SchallEndgameEvolution/control.lua:381: in function <SchallEndgameEvolution/control.lua:374>

This happens every time I click on the evolution stats

Thanks for the report.
I will need some more info from you:
1. What is your mod settings of this mod?
2. Does it happen if only this mod is enabled?
3. Are there any other mods modifying the vanilla biter spawners and spitter spawners? (There will a line of text in the right info panel, when selecting a spawner.)
4. Can you provide a list of enabled mods?

PS: I suspect maybe some conflict happens from another mod(s) modifying spawners. Have to investigate how it exactly happened.

1 My Mod settings were Normal difficulty and level 7 biters. After changing it to level 10 I started this issue
2 Yes
3 yes but uninstalling it has no effect
4 I'm using a lot of mods and it still happens when this is the only enabled

It is strange I cannot reproduce the error at all.
But anyway, I introduced a generic fix in the recent version 0.17.8. Please see if the problem is solved or not.