Mac OS Sierra
Even though the scripts seem to work fine on Mojave (MacOS 10.14), severe problems have been detected on a MacBook with Sierra (MacOS 10.13) installed (which has been identified thanks to a customer from the US). The error could not be reproduced on a Sierra-VM, though. Further investigations are necessary in order to find the root cause.
Data Directory for Audio Files
In Reaper it is possible to define a dedicated directory for the audio files in the project properties in order to separate the project files from the audio data. However, the MuCol-scripts can not handle this setup - so please do not apply this feature.
Session Strings Pro (Native Instruments)
Track has "Session Strings Pro" loaded in the "Kontakt"-plugin from Native Instruments. Track is marked with ">C" (copy tracks to instrument-project or vice versa) and project processing is launched ("MC-PP").
Reaper crashes half way through the process.
Save the setup in Kontakt (multi), remove the "Session Strings Pro", launch "MC-PP", load the saved multi in the copied track. Or replace the sound with e.g. "String Ensemble" (if available).
This problem occurs with the version 11 of Komplete. Version 12 is out and will be tested in the near future.
Working with subprojects.
While it is possible to create backtracks from tracks holding subprojects, it is not possible to copy those tracks to or from instrument-projects (">C").
Create stems instead of subprojects or create stems from the subprojects.