URL parameter of an embedded report -> overridable community connector config parameter

[jan_spudich]

Dear members of the Looker Studio community,

can you help me to solve the problem described below?

The goal is to embed a Looker Studio report into a web application, WA. The report uses a blend of two data sources which in turn are instances of a community connector which I have developed. The connector has two configuration parameters:

1. dataSet (newSelectSingle) - a choice of a dataset which a data source (i.e. an instance of the connector) returns.
2. aConfigParam (newTextArea) - an arbitrary text passed from WA (where the report is embedded) using the URL report parameters. Therefore the parameter is set as override-able using setAllowOverride(true) in the connector code.

The report data sources have been established as reusable (as opposed to embedded) and configured as follows:

1. Data source A
   1. dataSet - a data set A, say "projects"
   2. aConfigParam - no value set, the flag 'Allow to be modified in reports' ticked/set. 
      
      
   3. 
2. Data source B
   
   1. dataSet - a data set B, say "risks"
   2. aConfigParam - no value set, the flag 'Allow to be modified in reports' ticked/set. 
      
      
   3. 

The above data sources have been blended to create a data source for components of the report, e.g. a drop-down filter and a table.

The last step in configuring the report was to enable the override-able data source parameters to be set using the report URL parameters in the Looker Studio menu: Resources -> Manage report URL parameters. And here come the problems:

1. While yesterday I could see the two items which I could enable to be set using a report URL parameter, I cannot see any today. Neither the report data sources configuration nor the connector source code have changed between yesterday and today.
2. Yesterday, when I had the property 'Allow to be modified in report URL` set (which I cannot achieve today), the values of the data source config parameters (as set in the report query parameter params) did not find their way to the connector getData function anyway.

Using a simplified version of the procedure described above and using the same connector I managed to pass a value of a report URL parameter to the getData connector function if I use a single data source (as opposed to multiple data sources blended).

Having said all that, is there anybody out there who has managed to pass a value of a report URL parameter to a connector config parameter while the connector is instantiated multiple times and blended in the report? If so, I'd be grateful if you could share your knowledge and experience while achieving such setup.

Regards,
Jan