What about adding to the one option where the pop up is displayed on selecting the split, that an option for the entire screen is made available as well?

What about a global feature where ALL windows by default will not use the split, and/or an option where ALL windows WILL use the split?

I'm encountering more than a few windows/applications which present unexpected and undesirable behavior when the "X" button is clicked when associated with a split. HOWEVER, ALT+F4 works correctly. At a minimum, this feature really needs a quick fix by providing generating the ALT+F4 when "X" button is clicked event to actually close the window.

Has consideration been given to enhancing the "Process Filename" to supporting a LIST of "Process Filenames" I ask as there could be a significant number of "Process Filename" apps which a trigger would need to be generated, and more importantly managed.

For choosing which split (or full screen) an application starts on, I would recommend using the Triggers feature. Here are the basic steps to setup a Trigger rule:

Open the application
On the Settings > Triggers tab, click Add
Enable the "Process Filename" checkbox, then select the application from the "Select Application window"
In the Actions pane, click Add > Move Window to Selected Monitor and pick the split you want it to be on. You can then add the Maximize action, or Run Function > Maximize (ignore splits)
action depending on whether or not you want it to maximize to a split or the full monitor

The full guide on Triggers is here: Working with Triggers

Regarding the skinned apps not working correctly with the splits, this seems to happen if they are creating their own custom caption buttons, instead of using the Windows caption buttons. Unfortunately there's not much we can do there, but if the application allows you to double-click the titlebar to maximize/restore, that should work.

We've put a feature request on our list for the ability to have a specific application ignore the splits. So we'll definitely let you know when that's available.

Unfortunately it isn't possible for us to augment that "Run" drop-down on the shortcut properties

Ok, thanks! What if there was an extra option on/above/below the monitor that's split that would allow you to maximize to the full monitor instead of the splits? So instead of having to cycle between different split configurations in the monitor selector window, there would just be an extra option for ignoring splits?