PageAnalyzer in Ext JS 5?

I'm trying to track down some '[E] Layout run failed' errors in my app, and I saw in some previous posts that using the 'PageAnalyzer' might be helpful in tracking these down. The only reference to the PageAnalyzer is in a 4.1 Guide on optimizing performance. I tried to follow the instructions for using the tool, but when I try to run it I just get a blank screen. I can see that several .js files were loaded, but the only diagnostic output I get is two warning messages on the console from Util.js:

[W] Redefining field "text" in PageAnalyzer.models.LayoutTreeNode

[W] Redefining field "text" in PageAnalyzer.models.ComponentTreeNode

I'm using the Ext JS 5.0.1 SDK with the latest version of Sencha Cmd.

If PageAnalyzer doesn't work with 5.0.1, does anyone have any other suggestions for tracking down '[E] Layout run failed' errors? I'm trying to migrate an Ext JS 4.2 application to Ext JS 5.0.1 and things sort of work, but not quite.

Thanks!

Jim

PageAnalyzer in Ext JS 5?