I have several operations that are reused in different Organisational Processes. Is there a way to reuse these operations rather than recreating each time?
just drag and drop the already created operations on the diagram or when you add it through the diagram iconbar, start typing part of the name of the operation and hit ctrl+L to get suggestions of operations
Technically Operations are not Re-usable except on the same Diagram as they are owned by the Organizational Process.
If there is one that needs to be reused you can convert it to an Organizational Process and use it as a Called Organizational Process in other diagrams.