When adding groups, subjects, conditions, stimuli, elements, ... to an experiment, they seem not to be added. Worse, the same kind of IDs have disappeared from all other experiments as shown lacking + signs in the data view tree on the left side. A message tell:
Cannot add item
OK

CAUSE: A second Movalyzer is running and keeps one of the tables open.

REMEDY: Close the second Movalyzer.