Some additional things I've noticed (I am the owner of the image):
Yesterday I ran a new image of the same configuration. I worked from home, where I connect my laptop to a wireless router by AT&T.
I bridged the image to my wireless network, and when the image loaded I got the following message:
“Network service discovery disabled. Your current network has a .local domain, which is not recommended and incompatible with the Avahi network service discovery. The service has been disabled.”
After that, the new image showed the same problems as the previous one - logging to Thingworx Composer from the image directly or from a browser on my machine leads to an empty page with the Tomcat icon in the browser tab. Switching to a different network (tethered, office, Starbucks, etc.) and restarting the VM did not work I also tried some resolution suggestions I found online - none worked. Since then, the VM TWX is unusable.
Looks like this is the cause for the image to break.
(By the way, the Experience Server on both machines works well)
I am still looking for two outcomes from this "adventure":
1. Restore work from the image I shared with Liwei. The data is important for a project I am working on.
2. Understand how to avoid the issue that causes the image to stop working properly.
Thank you for your help!