Editing shaders.xr

[AffectedOne]

Hello,

I'm trying to create new map for my mod and i need to add new shaders for terrain in SDK. I tried yurshat repack, lost alpha sdk, yaras sdk, vanilla 0.4 sdk and even 0.7 call of pripyat sdk, but everytime game crashes after editing shaders.xr file. I know it must be something obvious i'm missing. Do i need any particular SDK to work with this engine, or any SDK can be adapted? Tried to look for answers, but could not find anything in english speaking part of the internet. I can read and understand a little bit of russian, but writing is very hard and wonky google translate does not help in searching russian forums. Sorry to bother you guys, but can someone point me in the right direction on what to do or where to look for more info.