Timeout when opening multiple structure superposition

When multiple structures for multiple sequence are opened simultaneously in a structure viewer (Jmol/Chimera). Superposition fails with the following error message "Timed out waiting for structure viewer to load file xyz". Accordingly, mappings are not generated and colours are not transferred, also mouse over highlighting doesn't work.

Update: There are two issues at work.
1. if some of the structures are not retrieved/opened then the Superpose step fails because not all structures are available. However, the structures should have been loaded and coloured *before* the superpose function is entered, and mouse over failure suggests problems during the loading/mapping process.
2. something is going wrong with the simplest feredoxin superposition example - since this is one of our tutorial exercises, fixing this is a priority for 2.9.1