You’re not doing anything wrong, I experienced the same problem over the last few days. I am actively working on a new version of the PCIbex Farm that should fix this issue, and trying to find a temporary workaround in the meantime, which will likely involve rebooting the servers and, as a result, possibly interrupting ongoing data collection (which is why I keep delaying it taking action…).
I apologize for this. In the meantime, you can try editing your code locally using a text editor and uploading the file back to your project. If this still does not work for you, consider hosting your experiments on the original Ibex Farm (note though that the Ibex Farm is not on a secure domain, so you won’t be able to access microphones and webcams, and you cannot upload resources directly to chunk_includes there).