[whpalmer4]

The UI for that didn't make it in 1.0, it's supposed to be in the follow-on release to clean up the various bugs found when everyone gets their hands on the app at long last. You can do it for projects, however.

To use the project editor to do this, edit the project containing the action group (aka sub-project), and tap on the action group. Tap the Move button, then Convert to Project. Now go focus on that project, edit it and set the parallel/sequential nature as desired, then tap the Move button and choose Convert to Action. This will send it off to your default Miscellaneous actions project, where you can edit it again to set the project back to where you wanted it. A bit clunky, but it shouldn't be this way for long!