Didn't found any discussions about mod, also invite link in CF page is broken as hell.

Also didn't find any information about validspawn condition usage. What the heck is this..

The invite link for Discord works perfectly fine. Just tried it
Anyway, here it is again: https://discord.gg/jaPZzxXY5Z

You need to update it here: https://www.curseforge.com/minecraft/mc-mods/in-control

Nope, that link works fine for me