Alright, everything are in order, the files extracted correctly using 7-zip.

I unable to start the game via the .exe file, but I able to do it from the .jar file. This my device specification:

and mine error.txt:

com.badlogic.gdx.utils.GdxRuntimeException: com.badlogic.gdx.utils.GdxRuntimeException: Couldn't load dependencies of asset: characters/HeavyTrainer1.png
at com.badlogic.gdx.assets.AssetManager.handleTaskError(AssetManager.java:570)
at com.badlogic.gdx.assets.AssetManager.update(AssetManager.java:375)
at com.majalis.screens.LoadScreen.render(LoadScreen.java:85)
at com.badlogic.gdx.Game.render(Game.java:46)
at com.badlogic.gdx.backends.lwjgl.LwjglApplication.mainLoop(LwjglApplication.java:223)
at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:124)
Caused by: com.badlogic.gdx.utils.GdxRuntimeException: Couldn't load dependencies of asset: characters/HeavyTrainer1.png
at com.badlogic.gdx.assets.AssetLoadingTask.handleAsyncLoader(AssetLoadingTask.java:121)
at com.badlogic.gdx.assets.AssetLoadingTask.update(AssetLoadingTask.java:90)
at com.badlogic.gdx.assets.AssetManager.updateTask(AssetManager.java:498)
at com.badlogic.gdx.assets.AssetManager.update(AssetManager.java:373)
... 4 more
Caused by: com.badlogic.gdx.utils.GdxRuntimeException: com.badlogic.gdx.utils.GdxRuntimeException: Couldn't load file: characters/HeavyTrainer1.png
at com.badlogic.gdx.utils.async.AsyncResult.get(AsyncResult.java:46)
at com.badlogic.gdx.assets.AssetLoadingTask.handleAsyncLoader(AssetLoadingTask.java:119)
... 7 more
Caused by: com.badlogic.gdx.utils.GdxRuntimeException: Couldn't load file: characters/HeavyTrainer1.png
at com.badlogic.gdx.graphics.Pixmap.<init>(Pixmap.java:148)
at com.badlogic.gdx.graphics.TextureData$Factory.loadFromFile(TextureData.java:98)
at com.badlogic.gdx.assets.loaders.TextureLoader.loadAsync(TextureLoader.java:69)
at com.badlogic.gdx.assets.loaders.TextureLoader.loadAsync(TextureLoader.java:41)
at com.badlogic.gdx.assets.AssetLoadingTask.call(AssetLoadingTask.java:70)
at com.badlogic.gdx.assets.AssetLoadingTask.call(AssetLoadingTask.java:34)
at com.badlogic.gdx.utils.async.AsyncExecutor$2.call(AsyncExecutor.java:58)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.io.IOException: Error loading pixmap: decoder init failed for stream
at com.badlogic.gdx.graphics.g2d.Gdx2DPixmap.<init>(Gdx2DPixmap.java:90)
at com.badlogic.gdx.graphics.Pixmap.<init>(Pixmap.java:146)
... 10 more

Mine laptop's relatively old. Thanks for whoever (especially the 'copyright holder' of this game) help with this problem.