Is there anything in the Indicium that can be traced back to this error? Normally these errors are available there as well, as you can debug it from there. 

Thank you ​@Jochem Pieper, but the log says nothing.

I have made a ticket with more details for this in TCP, hopefully it can be solved soon.

When this only occurs within certain screens, it might has something to do with either the screen components within the screen or expression fields/look-ups that are not working correctly. If there are open validations for screen types or something subject specific, make sure they are resolved before trying again. 
 

Thanks for creating a ticket in TCP, we will come back to that shortly.