The link at the top of the pages takes you to the Civil Engineering Community Center that now hosts videos.
Older webinar videos are available by paging through the list.
The link below takes you to the previous Infraworks Video page in the old Infraworks Community site
Old Infraworks Videos Page
What's New in Infraworks is always contains the latest updates.
See the Webcasts Page for sign-up details.
Jeff's post also included a links to an older AKN post How to recover an Infraworks Project with some more processes that might help.
Know your Autodesk product's AppData folder. I do tend try to remember to Duplicate Models at key points.
Autodesk's Jeff Bartels demonstrates organization and presentation basics by Feature Class Subsets in Infraworks.
Subsets in Infraworks allow you to organize feature class data into logical groups that can easily be selected, themed, or exported.
From the Jeff Bartels YouTube Channel.
and the Civil Immersion blog.