Soft synth plugin layouts

 
Here's a situation I have discovered regarding Plugin Layouts.  More specifically, the soft synth lists built from saved plugin layouts that appear in several submenus and the Sonar Browser.

I started from a mostly clean slate.  I just installed Manchester 1 in order to see if what I describe below is still a problem, or only in Kingston where I discovered it following another problem encountered by ChristopherM.  I created a new empty project.  After each change I saved the project, exited Sonar and opened the Registry.  Then closed the Registry before reopening Sonar.  It is actually only necessary to close and reopen regedit.
 
I created several plugin layouts to be able to track where they each appeared or didn't appear (widely different list lengths make visual identification easier).  I used layouts containing different combinations of only soft synths and one containing a mix of audio fx and soft synths (in which case, only synths appear in the resulting list).
 
Note:  I did not play with the "Default All Plug-ins" plugin layouts (for some reason I have two) that are offered in each of the submenus listing existing plugin layouts.  The default layouts are dynamic and subject to some processing that I did not look into.  They may have their own problems as can be read about in the above link.  In what follows, I only deal with fixed plugin layouts that I created using the Plugin Manager.

Background

Paths to function-specific plugin layouts are stored in the Windows Registry under :

HKEY_CURRENT_USER\SOFTWARE\Cakewalk Music Software\SONAR\Platinum\PluginMenuLayoutMRU

The keys dealing with soft synths are :

"SynthRackSynths"
"PluginBrowserSynths"
"TrackSynths"

Note : the "TrackSynths" key contains the path to the plugin layout used in a track's FX bin "Insert Soft Synth" submenu.  This submenu and its registry key appear to exist in a world of their own and I have found no problems with them.  They will therefore not be dealt with further in this post.

List and submenus involved :

Submenu (A)  Sonar's Main menu -> "Insert" -> "Soft Synth"
Submenu (B)  Browser -> [Synth tab] -> "+" -> "Insert Synth"
Submenu (C)  Browser -> [Synth tab] -> click Synth tab itself -> "Replace Synth"  (only with a synth selected)
Submenu (D)  Browser -> [PlugIns tab] with "Instruments" selected -> click PlugIns tab itself

List (E)  - the list of instruments displayed in the Browser [PlugIns] tab (when the "Instruments" button is selected/blue)

Submenus (A), (B) and (C) are internally linked and always display the same list of synths as specified in the plugin layout whose path is stored in the Registry key "SynthRackSynths".  A particular plugin layout can be selected from within any of these three submenus and they will all three change accordingly.

List (E) is built from the plugin layout selected in Submenu (D) whose path is stored in the Registry key "PluginBrowserSynths".

Context

Everything hinges on the state of the "Instruments" button in the [PlugIns] tab of the Browser.  This button turns blue when selected and a list of instruments then appears in the Browser.  The situation described below occurs only when this button is selected, whether or not the button is currently visible (it may be hidden because the [Media] or [Synth] tabs of the Browser are active, or the Browser itself is hidden) but if hidden, it must have been in the selected state before it was hidden.

The problem

With the Instrument button selected, assigning a specific plugin layout to any one of Submenus A, B or C (which assigns that plugin layout to all three submenus because they're linked) causes both keys "SynthRackSynths" and "PluginBrowserSynths" in the Windows Registry to receive as value the path to the plugin layout just assigned.  This has the effect of also changing the currently selected plugin layout for the Browser's [PlugIns] tab and the list of instruments displayed in the Browser will now be the same list as in Submenus A, B and C.
 
Similarly, always with the Instrument button selected, selecting a plugin layout from the submenu invoked by clicking the Browser's [PlugIns] tab will also erroneously cause the other three Submenus to adopt this plugin layout.

A special case within the problem

This special case only happens when the Browser "Instruments" button is visible (instrument list is then also visible in Browser), so it can only happen when selecting a plugin layout using Sonar's main menu (Insert->Soft Synth).  Otherwise the "Instruments" button will be hidden by the other tabs of the browser.

Also, the Instrument button must be newly selected ON  (ie, it wasn't selected beforehand, and was then clicked on).  This is very important.  For example, you can click on  the "Audio FX" button to unselect "Instruments" button, then click on the "Instruments" button to select it.
 
Now, select in Sonar's main menu :  "Insert" -> "Soft Synth" ->  "Plug-in Layouts" ->  "LAYOUT XX"

The "Soft Synth" submenu in the Main menu does not change, nor do Submenus B or C, but the List (E) visible in the Browser instantly adopts "LAYOUT XX".  Just as if the Browser [PlugIns] [Instruments] plugin layout had been selected.  Indeed, the Browsers's [PlugIns] tab submenu will now have "LAYOUT XX" checked as if it had been selected there.

Select again in Sonar's main menu :  "Insert" -> "Soft Synth" ->  "Plug-in Layouts" ->  "LAYOUT XX"

This time the "Soft Synth" submenu in the Main menu adopts "LAYOUT XX", as do the other soft synth Submenus (B) and (C).  This happens because, this time, the "Instruments" button was already selected.

The normal case

If the Browser "Instruments" button is currently not selected (hidden or otherwise), selecting a plugin layout within Submenus A, B or C will not affect the plugin layout selected in the Browser [PlugIns] (Instruments) submenu, nor the list of instruments displayed in the [PlugIns] tab.  And in the Windows registry, only the "SynthRackSynths" key will be modified.  Similarly, selecting a plugin layout in the Browser [PlugIns] (Instruments) submenu will update the list of instruments displayed in the Browser, without adversely affecting the other Submenus.  The path to this plugin layout is then also correctly stored in the PluginBrowserSynths registry key.
 
In closing
 
Whether or not it's useful to have three different soft synth lists (one for FX bins, one for the three submenus and one for the Instruments list in the browser) is another matter.  There is also a fourth Registry Key "Synths" that may be used for some other soft synth list but I don't know where it might appear in Sonar.  It is currently blank in my registry (which means "use the default list").  If anyone knows what it's for, I'll add it and its description to the list above.