RExpression actor doesn't output properly with >1 dataframe output port
If you configure the R actor to have more than 1 dataframe output port, only the last dataframe used is output through these ports.
For example, if I have actorA with data1 and data2 as dataframe output ports, and I feed these into input ports data1_in and data2_in on actorB respectively, actorB receives data2 twice.
This has to do with how data is serialized to disk (1 file per actor, instead of 1 file per port-that-serializes- to-disk), so the file for a given actor is currently overwritten each time data is serialized to disk for that actor.
We probably want to note this bug somewhere for Kepler 1.0 R actor users.
I have a local fix underway that is close to completion.