Looking into it, it seems like most of your issues stem from the fact that you depended on View._configure being called during initialization. You overwrite it here:

https://github.com/tbranyen/backbone.layoutmanager/blob/mast...

but this was completely removed with the update:

https://github.com/jashkenas/backbone/compare/1.0.0...1.1.0#...

In backbone's defense, that wasn't part of its public API, but it does make updating challenging. I'll give it a try and see if I can be of some help.