Thank you so much! Your modifications definitely make sense. On the C++ side I had to add ‘extern “C”’ to the printString function to get it recognized when the JS calls it. I also added:
GEngine->AddOnScreenDebugMessage(-1, 15.0f, FColor::Yellow, FString::Printf(TEXT("I got: %s"), &str));
(which I know you’re not familiar with, but has served me well during the rest of development) so that I can see the result onscreen in realtime (along with an alert in JS to verify execution).
So, now everything seems to trigger – I can trigger the JS from UE4, which in turn triggers the printString function back in UE4, and no errors get thrown along the way. Unfortunately, what still isn’t happening is the string being displayed. Instead, the data appears to be blank. I’m going to try and verify that my GEngine line is structured properly (so I know that it’s not misleading me), but is it possible that the string conversion is not working right, or maybe that the string isn’t getting placed into the “str” variable? Do you have any other ideas as to what might be going on? Thanks again!