<platform name="android">
    <!-- set Crosswalk default background color -->
    <!-- see http://developer.android.com/reference/android/graphics/Color.html -->
    <!-- <preference name="BackgroundColor" value="0xFFFF0000" /> -->
    <preference name="BackgroundColor" value="0x00000000" />
</platform>
[/code:tchgc4ej]
0x00000000 is supposed to configure the webview background color to be "transparent black"; at least according to the docs and the plugin code...
[code:tchgc4ej]
https://github.com/crosswalk-project/cordova-plugin-crosswalk-webview[/code:tchgc4ej]
[code:tchgc4ej]https://github.com/crosswalk-project/cordova-plugin-crosswalk-webview/search?utf8=%E2%9C%93&q=BackgroundColor[/code:tchgc4ej]
...and you should be able to set that color to anything you want. However, I was only able to get black and white out of it. It could be that setting it to fully transparent is having some other impact, I don't know and, honestly, don't have time to pursue this further at this time.

I see you were building against CW18, I did most of my testing against CW17 because I wanted to compare with a non-Crosswalk Android build on Android 5+, as well. So I had to remove your CW override in the additions.xml file (seems there is a bug with leaving that in on Android builds, I've informed XDK engineering). The white band appears to cause your "100% image" to bounce up and down momentarily, which the "transparent black" does not appear to do. I saw a similar "bouncing" with the Android webview, but no color band. All of this makes me suspicious that there is something else going on beyond just the color of the webview background.

Regardless, this solution appears to work.

Regarding the inability to effect the timeout value of the splash screen delay using the "SplashScreenDelay" directive, that is due to some code tucked inside the C2 lib file that is making a call to navigator.splashscreen.hide() during initialization. It appears there is no wait on the Cordova ready and document ready (at least as far as my limited investigation revealed). I will recommend a different approach to Ashley, because the approach in the code you provided does not give you a way to control that part of your app just using the delay directive.

<platform name="android">
    <!-- below requires the splash screen plugin -->
    <!-- see https://github.com/apache/cordova-plugin-splashscreen for details -->
    <preference name="SplashScreen" value="screen" />
    <preference name="AutoHideSplashScreen" value="true" />
    <preference name="SplashScreenDelay" value="10000" />
    <preference name="FadeSplashScreen" value="false"/>
    <preference name="SplashMaintainAspectRatio" value="false" />
    <preference name="SplashShowOnlyFirstTime" value="false" />
</platform>
[/code:2htlt6ph]
In particular, the 10000 value for the splash screen delay should delay the splash screen for 10 seconds, but only if the AutoHideSplashScreen is set to "true". 

Unfortunately, I don't know if Ashley is adding anything in the auto-generated app code to do something programmatically with the splash screen API, so I can't say with certainty this will last 10 seconds, but if he's not doing anything, it should last ~10 seconds. Then let me know if the splash screen "hides" that stuff or if it just gets tacked onto the 10 second delay. 

In other words, what I want to know is, by doing this, does it simply delay the appearance of the white bar by 10 seconds or do you no longer see the white bar (because it's "behind" the splash screen). In either case, the splash screen should last for ~10 seconds. If it does not last for ~10 seconds, I want to know that, as well.

Thanks.

<preference name="AutoHideSplashScreen" value="true" />
[/code:1no0ocfi]
The splash screen plugin includes an API that can be used to effectively "synchronize" the completion of Cordova and Construct2 game initialization, so the splash screen remains until everything is ready to run. However, to use that technique, you need to understand how to write custom JavaScript in your C2 app AND know how to recognize when the Cordova bit is initialized as well as when the C2 bit is initialized. To synchronize the splash screen with just the Cordova init, you would set the line I show above to "false" and do something like this in your app:

[code:1no0ocfi]
function onAppReady() {
    if( navigator.splashscreen && navigator.splashscreen.hide ) {   // Cordova API detected
        navigator.splashscreen.hide() ;
    }
}
document.addEventListener("app.Ready", onAppReady, false) ;
// document.addEventListener("deviceready", onAppReady, false) ;
// document.addEventListener("onload", onAppReady, false) ;[/code:1no0ocfi]

See the Cordova splash screen plugin for complete documentation > https://github.com/ apache /cordova-plugin-splashscreen (remove the spaces in the URL, I don't have enough points to post URLs on this forum).