Hm, i can open then on 2022.3.4f1 just fine 
I’ll download the latest and try again.
Maybe something specific to MacOS?
Trying again in a new project, let’s see
by user 832577308644212766
You can manually find the scene in Needle engine Samples / Runtime / SAMPLE_NAME and drag it into the Assets folder, it will duplicate the asset, then open it. As a temporary workaround.
Alternative would be to create a new project on 2021.
Any errors in the console, forgot to ask.
Do you have enough space? Is the project in a writable space and such?
I i’m not a mac os user for some time, so bare with me 
Console showing this error: Instance of ExportInfoEditor couldn't be created. The script class needs to derive from ScriptableObject and be placed in the Assets/Editor folder.
by user 832577308644212766
On Windows 2022.3.11f with the latest samples running on 3.21.0 does work so it is possibly OS X specific.
What OS X version do you have?
Yes, the release is stable 
Sonoma 14.0
by user 832577308644212766
Finally made a sample correctly playing/exporting in Unity 
by user 832577308644212766
Stupid question: what if I want to play the sample just in Unity (not exporting to browser)?
by user 832577308644212766
If there’s some custom logic in the sample it is made in Typescript for the web only, so it won’t work in Unity.
But you are able to maintain yours like that allowing for multiplatform deploy and leveraging Needle for the web.
Do you mean that the .ts scripts are ignored when running inside Unity?
by user 832577308644212766
Yes, those are not utilized.
For example I was trying the sample ShootingRange inside Unity. The player falls down as the rigidbody/collider is ignored
by user 832577308644212766
