Continuing from this thread I started over a year ago - I thought It would be best to start a new thread, as a number of things have changed.
Seeing how close we are to landing here, I thought I would make yet another attempt to create a V8 personalized workspace - starting from scratch but integrating some of the customizations from my V7 workspace. Note, having imported a .rui a long time ago, I already have a working copy of my V7 workspace running currently, but it’s all bitmap icons plus it needs some revamping in any case.
I’m writing this out to get some advice, but also to get clear in my own mind* what needs to be done and how. *Right now it’s still pretty foggy in here… 
To recap, in V7 and earlier everything concerning toolbars (except their placement) was contained in the .rui file. This made it easy to customize and back up/transfer – only one file to deal with. My V7 custom workspace is – like most other peoples’ I think – a copy of the default toolset in which new buttons and toolbars have been added and (perhaps) some of the originals modified by changing the macro behind the button or modifying the image or both.
Given the structure of the V8 setup where the default toolset is now no longer a separate file and cannot be closed, this poses a number of questions/problems to solve.
Adding new (custom) toolbars:
My current thought is that I can export some of the completely custom toolbars from V7 as an .rui file and open that in V8. Later on, I can start replacing the bitmap icons with .svg. In my case, many of these buttons are text-only anyway that run certain scripts.
Modifying existing tools/toolbars:
Ay, there’s the rub. It seems like it is possible to modify the default toolbar library’s tools - I did it in the past under a test scheme and it still seems to be working. Assuming it’s still possible, can one change a macro or the icon image on a button in the default toolbar library or add an additional button to an existing toolbar - and be assured that these changes will be saved and guaranteed not to be nuked if for some reason a reset is necessary? And if we modify the default toolbar library in this way, then it’s not really default anymore… is it?
The current solution that allows me to run my V7 .rui in V8 is simply that all of the default library toolbars are closed (like default doesn’t exist) and only the ones from my custom .rui are open. This way, anything custom is currently completely independent from default.
So the idea for a rebuild/customize from scratch might be to make a copy of ‘default’ under another name, open it from Appearance>Toolbars and start modifying it. I see there is an entry for “Export RUI File…” under the Tools menu (and also a command) and looks like the default toolbar library is exportable…
That might be the way forward for me.