Fixes

• Attempt to fix a rare condition in which the countdown to end of sequence actions dialog might hang and prevent end of sequence actions from running. In this version, it is still possible that the UI dialog might hang but this should no longer prevent the sequence from executing end of sequence actions. This is a temporary safety fix.
• Made some changes to address scenarios where modal dialogs might appear behind other windows like the sequencer form or the control panel effectively locking the UI.