Sounds like this needs to be included in my next Sonar column for Sound on Sound. Thanks, Noel!

I was expecting Scott to answer this one http://forum.cakewalk.com/FindPost/2885110

John T
The most obvious implementation, I reckon, would be the ability to set it in the plugin container.

The default preset is stored in the plugin menu xml. Once a plugin is inserted however, we have no idea where it came from so it wouldn't know how to save the default preset anymore. That's why its in the layout editor...

Noel - I can't get this to work. Depending upon the plug-in in question, either there are no presets available in the pull-down in Properties (your step 8) and <none> is displayed, or there are presets available, but later when I instantiate the plug-in from that particular Plug-in Menu, the plug-in loads with whatever its regular default settings happen to be.
 
I assumed that "default settings" was an arbitrary name for the preset, but does it have to be so? Also, what folder location does the "default settings" preset have to be in before it appears in the Properties pull-down?

If the layout editor doesn't see the preset then you are not saving a Cakewalk plugin preset.  Make sure you are saving a preset from the toolbar at the top of the effects UI window, by typing in a name and clicking the save icon. i.e. the preset has to be a Cakewalk preset. If you save a preset from the plugin UI itself SONAR has no way of seeing the preset.
The name of the preset is arbitrary. You can name it anything you want. 

Noel - Thanks, but I am doing exactly what you say (I think!). To keep things simple, I am working with Channel Tools (as it already has Cakewalk presets). I select Increased Width preset in the Properties pull-down, then Save As ... and overwrite the menu in the Layout Editor. If at a later point, I re-open the same menu in the Layout Editor, I can see Increased Width displayed in the Properties pull-down. However, if I use that layout then to insert Channel Tools in, say, a Bus FX bin, the plug opens with "no preset" displayed in the header (and it certainly is not Increased Width by any other name, either).
 
I get exactly similar results with non-CW plugs, too.
 
Any clues, please?

This didn't work for me at first either. I had to double-click in the name dropdown and it went editable. I entered the text for my name and clicked the Save icon. After that, the preset appeared properly in the templates editor and worked like a charm! 
 
It's a bit of a convoluted process - if this could be integrated right into the plugin interface, you'd have a real winner! Put it in X4 and most people will think it's a new feature. ;)

It didn't seem to work right for me at first either, I had to make sure I didn't forget a step.
 
I think there might be a simpler workflow for this and will post if successful.

I have to re-iterate - this is an AWESOME hidden feature. It's already saving me a lot of time and frustration. I am using VUST VU meters before and after each plugin to get my metering right. Now the VU meter loads with my custom colors, peak and fall times, and with the hold needle visible. This was a pain in the ars before I learned this trick...

You might find this workflow easier:
 
1. Insert the plug-in and set it up as desired.
2. Save your default settings as a preset from the effects window’s top toolbar: double-click in the preset name field, type in a name like “Default Settings,” then click on save (the floppy disk icon).
3. Choose Utilities > Cakewalk Plug-in Manager.
4. Call up a Layout File containing the plug-in whose default preset you want to load. Note that each plug-in can have different default presets in different layouts.
5. In the layout’s plug-in tree on the right, find the plug-in from step 1.
7. Right-click on the plug-in name and choose “Properties...”
8. In the properties dialog choose "Default Settings" from the Default Preset drop-down menu.
9. Click OK, then save the plug-in menu layout you selected in step 4. When that layout is open, the plug-in will open with the default preset when inserted.