As I edit an experiment using 4.0.2 on a Mac, I find that sometimes after selecting a trial I’m unable to activate the event list by clicking or tabbing. Similarly, selecting a block appears to sometimes make it impossible to select a trial and/or event from their respective lists.
Sorry if there’s something obvious, but is this a bug or an aspect of the interface I’m not understanding?
It’s a bug. The behavior was improved with 4.0.2, but not completely fixed. If you close the experiment window and reopen it, your experiment should work again. This can be a bit annoying, though. A more permanent fix is to disable full keyboard access in the System Preferences (System Preferences->Keyboard & Mouse->Keyboard Shortcuts->Text boxes and lists only).
If you would rather leave this feature generally enabled, you can disable it for just SuperLab by pasting the following in a Terminal window: