Connect to SAP Business One Service Layer

We are trying out the features of AppGyver via the Community (Free) version. Don’t expect that this issues is related to limitations though.

We want to consume oData from the Service Layer of SAP Business One. Have come across two important issues:

Issue 1 (Login):
You usually want to start a session with Service Layer by calling the Login function and receive a session ID and a routeid in a cookie. This is not an oData call but a POST call to the Login service as a REST API. The call works fine, but it’s not possible to get hold of the cookie. Is that a limitation?

Usually a cookie like this would be handled by a web browser so that you don’t need to apply it to the consequent calls, but this doesn’t work wit the combination of REST API and after that oData calls. Right?

We found a way around, since it seems like the oData call will actually work ok, if we add Basic authorization to each call. Not the normal way, but seems to work. Any comment to this procedure?

Issue 2: We can read data, but not create/update:
Calling the GET method of the oData functions will work ok, but any PATCH call will not. We get an error back from the Service Layer as an error 405 HTTP Method not allowed. From Postman we can make the PATCH call and we have made the CORS settings in the Service Layer.

Could anyone suggest what is the issue here?

Anyone with input to these issues?