EHRbase - stuck in loading data

Hi. According to the docs on loading data, I have succesfully filled the ehrbase with data. But I got stuck on one of the addes section:

https://tools.openehr.org/designer/#/viewer/shared/Pz9zaGFyZWRJZD0xJGZlYWU3Zjg3NTUzZDQxNWQ4NTE1MmFkYTk0MjNkNWY1

After trying to send data in flat format, I got response:

{
    "error": "Internal Server Error",
    "message": "An internal error has occurred. Please contact your administrator."
}

And logs in terminal:

 java.lang.NullPointerException: Cannot invoke "String.startsWith(String)" because "nodeId" is null...

I am not very into java (mostly python) so I am not sure where to follow on that. Could you help?

Thank you

Can you please post templates and failing example compositions?

Sure. Here is the opt and composition file.:
https://drive.google.com/drive/folders/1WL1uGavh_wgccS1ZW1atemDUzehqQlGs?usp=share_link

Thank you.