I was just upgrading to the lastest HotPot and TaskChain. The HotPot completed fine. However, the Taskchain shows "Upgrading to new version - Moodle 2.5" and the window just shows mod_taskchain and does not change after several minutes.
If I go back into Notifications, it shows that the database needs to updated for the new TaskChain. Clicking on that gets back to the same situation.