Here is the script updated for 4.0. 
https://drive.google.com/file/d/1bSHc8KzHAFVbt3i3bbr1twNMP0IZoMvx/view?usp=sharing

All I did was change the Props a little. 
From:    row.prop(context.active_object.data, "layers", index=16, toggle=True, text="Root")
To:         row.prop(context.active_object.data.collections["Layer 17"], "is_visible", toggle=True, text="Root")
instead of using index you use the collections name. I could have use Root, Squash, Body, and Spin. Warp is divided to Warp_01 and Warp_02. I'm not sure if those bone collections will carry over in the stable release, but the Layer # is the defined method set by the devs. 

Thank you very much for all the comments and the ultra-fast solution from Dwayne Savage. (Thank you). I am really impressed. 

I was expecting a simple "Yes..." or "No".

It is particularly interesting to me how differently the idea of "experimental blender builds" is viewed.

I would like to respectfully disagree with one statement. The daily builds are used by curious Blender users not only by developers... 

e.g. I finished a complete (commercial) project with a completely unstable Blender version, with many crashes, but it was the only way to use the new features. 

Without these unstable versions I would have had no chance to finish the project on time (long time ago, one of the first eevve Builds).

I think the point Adrian was trying to make was that while learning blender, it is better to use a stable release.  With that said, yes Peter the experimental versions are used by users. It is used by addon developers to test and update their addons. It's used for content creators so they can prepare videos for new releases. It's used by users so they can test and report bugs and hardware issues. This is one of the ways those of use who can't afford to donate can give back to the Blender Institute. It can also be used for production. Although it's not recommended. It's definitely used by people who want to play with new features. I've been playing with the new bone collections and bone collection custom properties, and one day I'm going to sit down and actually learn python. I've just pieced together things from blender's templates and the development extra's view source. 

Thanks Wayne Dixon and also how do you create proxy in this version of Blender i have failed

thanks Wayne Dixon let me try sir