In RM 5.2 double clicking on the source symbol the double click acton opened the Repository Browser. Currently (in RM 5.3) it does nothing. Was this intentional? (I could not find this change in the release notes.) Or it just just a configuration change related to the upgrade?
yes this was intentional. We just forgot to mention it in the changes, sorry for that. I have added it to the changes, thanks for reporting.
The reason it has vanished is, that we wanted to have equal and consistent behavior for input and output sinks of processes and subprocesses.
Now you have to right click on them and select 'Connect input ...'.