CoreFramework | Common core framework for implementing Global Illumination | Graphics library

appinstaller is just a file that is meant to be used for downloading actual resources (package) from web (https://docs.microsoft.com/en-us/windows/msix/app-installer/web-install-azure).

I think in your scenario distributing just .msix package should be sufficient. .msix file contains all you need to install and run the app.

There is also "issue" with certificate. Maybe running install powershell script could be an option

This request requires businessunitid in the payload.

Suppose I have an Output Parameter with name 'Result2'. Following is the code to send output parameter to custom action-

According to the code and picture you provided, in the postman, you use the OAuth 2.0 code grant flow to require Azure AD access token. The way is getting access on behalf of a user. The token is user token. But in your application, you use the method acquire_token_with_client_credentials to require Azure AD access token. It means that you use OAuth 2.0 Client Credentials Grant Flow to require Azure AD access token. The way is getting access without a user. The token is app token. They are different.

Besides, according to the error, you do not have enough privilege and you need to configure the permissions. It means that if you still want to use OAuth 2.0 Client Credentials Grant Flow to require access token, you need to provide enough privilege for the service principal(the AD application ) you use. Or you change your code to use OAuth 2.0 code grant flow to require access token. For more details about how to change, please refer to the sample

Nothing looks wrong except the extra white lines between Batch request unique identifier & headers, the error maybe coming because of that. Remove the extra white lines like below:

By our testing, we packaged the app into app bundle and then we deleted the dependencies in the dependencies folder under package folder. After that, we installed the app, it will prompt a message showing we need to install those dependencies. So we installed the dependencies manually and installed the app again, it worked this time. At last we uninstall the app and tried to re-install it, it also worked well. So you can also try this way-manually install the dependencies to avoid installing dependencies over and over.

I'm able to create a new customeraddress using below snippet & payload. I recommend you to use CRM REST Builder

No way. No parent no child. Without sales order why someone need sales order details?

Documentation says salesorderid is SystemRequired.

Update:
In fact salesorderid is the only required value to create salesorderdetails (Order Product) record. I tested the below snippet in CRM Rest builder.

Got it, issue was improper fields in the request body. This one works.