Use portable Chrome v.18, it also embeds Flash Player. If you need ActiveX support (IE behavior within Chrome, very useful for FSO FileSystem Object access, and reliable audio), install Neptune for Webkit over there. Then, create a shortcut to Chrome.exe. Right-click on it > Properties, then define the Target with this logic:
C:\...yourpath...\GoogleChromePortable.exe --kiosk http:/ /www.yourappurl.com.
--kiosk allows Chrome to open in full-screen mode (equivalent to F11) automatically (Alt+F4 to close), and disabling some keyboard shortcuts, and the http:/ /www.yourappurl.com is where you define the hosted or local path URL to your app/game/website. That means, this website will automatically open in kiosk mode when that shortcut is clicked.
To get rid of the kiosk mode, you can set back the value to -k instead of --kiosk. Chrome will now open normally.
As you are using a portable version of Chrome, you can distribute the Chrome files along with your app files. This ensures that your app will always be opened with Chrome, and it gives the professional look of an .exe file, while in fact it is only a simple browser shortcut. You can also change the name of the shortcut for the one of your app, and change the shortcut's icon graphic.
Enjoy professional distribution of any HTML4/HTML5 app ;)
I personnally had the same problem, and after learning and testing a lot with Adobe Air and Titanium Appcelerator (as well as many others, like HTMLEXE, QT, etc.), I found this useful, reliable, easy and professional way to distribute my HTML4 and HTML5 games :)