I need a guide on how to use Graphics5.

Here's my attempt below (I followed the Kha 3D tutorial by Lubos Lenco):

package exp;

import kha.Framebuffer;
import kha.Color;
import kha.Shaders;
import kha.graphics5.RenderTarget;
import kha.graphics5.TextureFormat;
import kha.graphics4.DepthStencilFormat;
import kha.graphics5.CommandList;
import kha.graphics5.PipelineState;
import kha.graphics5.VertexStructure;
import kha.graphics5.VertexBuffer;
import kha.graphics5.IndexBuffer;
import kha.graphics5.FragmentShader;
import kha.graphics5.VertexShader;
import kha.graphics5.VertexData;
import kha.graphics5.Usage;
import kha.Image;

class Scene {
	public var width:Int;
	public var height:Int;
	public var commands:CommandList;
	public var renderTarget:RenderTarget;

	var vertexBuffer:VertexBuffer;
	var indexBuffer:IndexBuffer;
	var pipeline:PipelineState;

	// An array of 3 vectors representing 3 vertices to form a triangle
	static var vertices:Array<Float> = [
	   -1.0, -1.0, 0.0, // Bottom-left
	    1.0, -1.0, 0.0, // Bottom-right
	    0.0,  1.0, 0.0  // Top
	];
	// Indices for our triangle, these will point to vertices above
	static var indices:Array<Int> = [
		0, // Bottom-left
		1, // Bottom-right
		2  // Top
	];

	public function new(width:Int, height:Int) {
		this.width = width;
		this.height = height;

		this.commands = new CommandList();
		this.renderTarget = new RenderTarget(width, height, 0, true, TextureFormat.RGBA32, NoDepthAndStencil, 0);

		// Define vertex structure
		var structure = new VertexStructure();
        structure.add("pos", VertexData.Float3);
        // Save length - we only store position in vertices for now
        // Eventually there will be texture coords, normals,...
        var structureLength = 3;
	
		// Compile pipeline state
		// Shaders are located in 'Sources/Shaders' directory
        // and Kha includes them automatically
		pipeline = new PipelineState();
		pipeline.inputLayout = [structure];
		pipeline.fragmentShader = cast Shaders.simple_frag;
		pipeline.vertexShader = cast Shaders.simple_vert;
		pipeline.compile();

		// Create vertex buffer
		vertexBuffer = new VertexBuffer(
			Std.int(vertices.length / 3), // Vertex count - 3 floats per vertex
			structure, // Vertex structure
			Usage.StaticUsage // Vertex data will stay the same
		);
		
		// Copy vertices to vertex buffer
		var vbData = vertexBuffer.lock();
		for (i in 0...vbData.length) {
			vbData.set(i, vertices[i]);
		}
		vertexBuffer.unlock();

		// Create index buffer
		indexBuffer = new IndexBuffer(
			indices.length, // 3 indices for our triangle
			Usage.StaticUsage // Index data will stay the same
		);
		
		// Copy indices to index buffer
		var iData = indexBuffer.lock();
		for (i in 0...iData.length) {
			iData[i] = indices[i];
		}
		indexBuffer.unlock();
	}

	public function update() {}

	public function render(frame:Framebuffer) {
		// A graphics object which lets us perform 3D operations
		var g = frame.g5;

		// Begin rendering
		g.renderTargetsInvertedY();
		g.begin(renderTarget);
		commands.begin();
		// commands.setRenderTargets([renderTarget]);
		// commands.renderTargetToFramebufferBarrier(renderTarget);

		// Bind state we want to draw with
		commands.setPipeline(pipeline);

		// Bind data we want to draw
		commands.setVertexBuffers([vertexBuffer], [1]);
		commands.setIndexBuffer(indexBuffer);

		// Draw!
		commands.drawIndexedVertices();
		// commands.clear(renderTarget, Color.Yellow);

		commands.end();
		// End rendering
		g.end();
		g.swapBuffers();
	}
}

I tried to build on MacOS Mojave, but the app crashed.