Migrating to WKWebView - Lots of Errors

I am following the tutorial on upgrading here: https://github.com/driftyco/cordova-plugin-wkwebview-engine#installation-instructions

This is party of my config.xml

 <preference name="webviewbounce" value="false" />
    <preference name="UIWebViewBounce" value="false" />
    <preference name="DisallowOverscroll" value="true" />
    <preference name="android-minSdkVersion" value="16" />
    <preference name="BackupWebStorage" value="none" />
    <preference name="SplashScreen" value="screen" />
    <preference name="SplashScreenDelay" value="1000" />
    <preference name="ShowSplashScreenSpinner" value="false" />
    <preference name="StatusBarOverlaysWebView" value="true" />
    <preference name="xwalkVersion" value="19+" />
    <preference name="xwalkCommandLine" value="--disable-pull-to-refresh-effect" />
    <preference name="xwalkMode" value="embedded" />
    <preference name="xwalkMultipleApk" value="true" />

These are errors I am getting:

2016-09-04 18:52:00.148 SaveUp[637:186902] Apache Cordova native platform version 4.2.1 is starting.
2016-09-04 18:52:00.149 SaveUp[637:186902] Multi-tasking -> Device: YES, App: YES
2016-09-04 18:52:00.262 SaveUp[637:186902] CDVWKWebViewEngine: trying to inject XHR polyfill
2016-09-04 18:52:00.276 SaveUp[637:186902] CDVWKWebViewEngine will reload WKWebView if required on resume
2016-09-04 18:52:00.276 SaveUp[637:186902] Using WKWebView
2016-09-04 18:52:00.277 SaveUp[637:186902] [CDVTimer][handleopenurl] 0.127971ms
2016-09-04 18:52:00.280 SaveUp[637:186902] [CDVTimer][intentandnavigationfilter] 2.857029ms
2016-09-04 18:52:00.281 SaveUp[637:186902] [CDVTimer][gesturehandler] 0.311971ms
2016-09-04 18:52:00.281 SaveUp[637:186902] CDVPlugin class CDVSplashScreen (pluginName: splashscreen) does not exist.
2016-09-04 18:52:00.281 SaveUp[637:186902] [CDVTimer][splashscreen] 0.097990ms
2016-09-04 18:52:00.281 SaveUp[637:186902] CDVPlugin class CDVStatusBar (pluginName: statusbar) does not exist.
2016-09-04 18:52:00.281 SaveUp[637:186902] [CDVTimer][statusbar] 0.075042ms
2016-09-04 18:52:00.281 SaveUp[637:186902] CDVPlugin class IonicKeyboard (pluginName: keyboard) does not exist.
2016-09-04 18:52:00.281 SaveUp[637:186902] [CDVTimer][keyboard] 0.072956ms
2016-09-04 18:52:00.283 SaveUp[637:186902] [CDVTimer][TotalPluginStartup] 5.887985ms
2016-09-04 18:52:01.765 SaveUp[637:186902] CDVPlugin class CDVDevice (pluginName: Device) does not exist.
2016-09-04 18:52:01.765 SaveUp[637:186902] ERROR: Plugin 'Device' not found, or is not a CDVPlugin. Check your plugin mapping in config.xml.
2016-09-04 18:52:01.765 SaveUp[637:186902] FAILED pluginJSON = ["Device1123549243","Device","getDeviceInfo",[]]
2016-09-04 18:52:01.767 SaveUp[637:186902] CDVPlugin class CDVStatusBar (pluginName: StatusBar) does not exist.
2016-09-04 18:52:01.767 SaveUp[637:186902] ERROR: Plugin 'StatusBar' not found, or is not a CDVPlugin. Check your plugin mapping in config.xml.
2016-09-04 18:52:01.767 SaveUp[637:186902] FAILED pluginJSON = ["StatusBar1123549244","StatusBar","_ready",[]]
2016-09-04 18:52:03.518 SaveUp[637:186977] CDVWKWebViewEngine: XHR intercepted: build/app.html
2016-09-04 18:52:03.738 SaveUp[637:186936] CDVWKWebViewEngine: XHR intercepted: assets/i18n/de.json

How to resolve?

same issue here with ionic2 app, any solution so far? Thanks for any help!!

Seems like a dead or dormant project, the github site has gazillions of issues, we are sticking to normal webview for now.