en: Idk what to say about this game. It's so silly and so charming. I was really enjoying the gameplay until the game crashed. I was like "Damn, completing entire mission again". But when i tried to launch it again, i got this cuttie
After few hours spent with futile attempts to fix the game, I was ready to give up. But finally I found the solution and want to share everything I've learned with you.

ru: не знаю, как описать эту игру. Одна достаточно глупая, чрезмерно пафосная, но этим она и очаровывает. Перчик начинал дымить, когда я получил первую ААА оценку задания и я уже начинал входить во вкус, как на боссе в 3 миссии я словил краш. Это меня озадачило, ведь мне предстояло перепройти уровень сначала. Наивно было думать, что это моя главная проблема. При перезаходе я банально словил очередной краш, после чего больше не мог зайти в игру. Выглядело это чудо как-то так
После нескольких часов поиска информации в интернете и перепробовав уже и hex эдитор и магию вуду, я было уже сдался. Но вдруг я нашел тот самый совет, который позволил мне вновь начать игру. И я хочу им поделиться.

en:Time to beat this demon a.k.a. "runtime loop detected"!
Method 1(worked for me):

1. Go to "%steam folder%\steamapps\common\KillerIsDead\KidGame\SaveData"
   
2. Find "KID.sav"
   
3. Сruelly delete it

I know, I know. You will lose your save. But do you really need it, if you can't launch the game?
Maybe, it's way too radical, so you should try method 2 first.

Method 2:

1. Go to "%steam folder%\steamapps\common\KillerIsDead\KidGame\Config"
   
2. Find "KidEngine.ini"
   
3. In [XAudio2.XAudio2Device] section use this parametrs
   MaxChannels=64 CommonAudioPoolSize=320 MinCompressedDurationGame=0.3 MinCompressedDurationEditor=500 LowPassFilterResonance=0.9 WorkAroundXDKRegression=FALSE

If this doesn't work, try to

1. Download this[community.pcgamingwiki.com] file
   
2. Go to "%steam folder%\steamapps\common\KillerIsDead\Binaries\Win32\"
   
3. Replace KidGame.exe with the crashfix.

This also help if you cannot pass the third boss.
If method 2 didn't fix the problem I recommend to use method 1.

There is one more bug that I know how to fix.
If you're using ♥♥♥ voice and sometimes it plays some sound in eng, you should

1. Open "%steam folder%\steamapps\common\KillerIsDead\KidGame\Config\KidEngine.ini"
   
2. Change Language from INT to JPN

That's all with fixing bugs.

Raise frame rate smoothing value and QTE values

1. Open <path-to-game>\KidGame\Config\KidEngine.ini
   
2. Find MaxSmoothedFrameRate and replace the value with bit over desired value (e.g. 60 FPS, put 62)
   
3. Save your changes and mark the file as Read Only to prevent game for resetting the value
   
4. Open <path-to-game>\KidGame\Config\DefaultGame.ini and update the Mika-Revive QTE by changing mRevive values:
   60 FPS
   
   Change mRevive_MassageRecoveryRate to 2.6 Change mRevive_MassageHealtDownRate to 0.98 Change mRevive_MassageDownPowerMax to 10.0
   120 FPS
   
   Change mRevive_MassageRecoveryRate to 5.2 Change mRevive_MassageHealtDownRate to 0.96 Change mRevive_MassageDownPowerMax to 20.0
5. Save your changes and close the file.

Set resolution and FOV

1. Open "%steam folder%\steamapps\common\KillerIsDead\KidGame\Config\KidEngine.ini"
   
2. Change ResX= and ResY= to the desired values(from 800x600 to 1920x1080)
   
3. (optional)Use Flawless Widescreen[www.flawlesswidescreen.org] to fix the FOV and HUD scaling

I hope it'll help you to fix crashes and to adjust game settings. Most info was taken here[pcgamingwiki.com].
Thanks for reading this far.

P.S. русскую часть ВОЗМОЖНО когда-то доделаю. Но главное, что переведено вступление, в дальнейшем все ясно и без перевода.