There's no delay whatsoever on my PC, the preview starts instantly, and there are no errors in the console log.
Do you have this delay when running other projects, say, C3 examples like the Kiwi Story? Maybe your Chromebook is just too slow.
From the Google Play screenshot, it looks like the MainMenu layout loads and some of the graphics appear (the blue tiled background), but other sprites and text are missing. I have no idea why this happens. Have you tried building an APK and running it on your phone?
There is one problem I noticed - you are using Fantasy font. You need to add it to the project, and make sure all text objects are using the project font, not the system one.