Initial Load on non GFX Laptop (Unity 2019.3.01f)

[phpchess]

Hi,

I am having some issues overcoming Entities errors. As a new kid to ECS & DOTS and coding and so on, this is probably past my capabilities. The exe described in your blog does not execute on my laptop, and in the project I am getting errors on Entity creation.

I have in my packages list:
"com.unity.2d.sprite": "1.0.0",
"com.unity.2d.tilemap": "1.0.0",
"com.unity.addressables": "1.1.10",
"com.unity.ads": "2.0.8",
"com.unity.analytics": "3.3.2",
"com.unity.collab-proxy": "1.2.16",
"com.unity.entities": "0.3.0-preview.4",
"com.unity.ext.nunit": "1.0.0",
"com.unity.ide.rider": "1.1.0",
"com.unity.ide.vscode": "1.1.3",
"com.unity.inputsystem": "1.0.0-preview",
"com.unity.physics": "0.2.4-preview",
"com.unity.purchasing": "2.0.6",
"com.unity.render-pipelines.universal": "7.1.5",
"com.unity.rendering.hybrid": "0.1.1-preview",
"com.unity.test-framework": "1.1.3",
"com.unity.textmeshpro": "2.0.1",
"com.unity.ugui": "1.0.0",

but I get errors:
ArgumentException: The entity does not exist
Unity.Entities.EntityComponentStore.AssertEntityHasComponent (Unity.Entities.Entity entity, Unity.Entities.ComponentType componentType) (at Library/PackageCache/[email protected]/Unity.Entities/EntityComponentStoreDebug.cs:231)

and warnings in the editor:
Assets_Project\Scripts\CameraEntityBridge.cs(25,25): warning CS0618: 'World.Active' is obsolete: 'World.Active has been deprecated. The most common & incorrect usage has been to use World.Active from a ComponentSystem. From a ComponentSystem you should use the ComponentSystem's World property directly. It returns the world that this system belongs to. There are some rare cases where a MonoBehaviour needs to inject data into the active world, in this case use World.DefaultGameObjectInjectionWorld. (RemovedAfter 2020-01-22)'

Clearly I am missing something. Sorry - maybe this is not a package error, but an "end user is thick" error. Any help is appreciated :)

[phpchess]

Just to be clear. I can load Level 1, but get errors on all other screens. Also errors occur on the level but it does not stop the initial gameplay, until shooting stops due to entity issues.