LabTutor Server cannot be used to edit experiments.
Experiments can be edited using LabAuthor, which is part of LabTutor 4 Teaching Suite of software. Edited experiments can then be uploaded to LabTutor Server and added to a course via the 'Upload an Experiment' tab.
For problems with experiment functionality refer to the LabAuthor Help that is installed with the LabAuthor application.
This information is valid for LabTutor v4.0 or later.