Hi M
That is the normal behaviour. aiStarter readies the impending communication between App Inventor and the Emulator.
From the Title of your Topic, are you expecting App Inventor itself to be run via aiStarter? That is not the case because App Inventor is Web Based software which you access via your Web Browser (Chrome, Firefox or Safari, no other Browsers are compatible.)
When you want to make a quick test of something in the App you are creating, run aiStarter from your desktop and then in App Inventor select Connect, Emulator.
If you are really new to all this, do the MIT tutorials first - they are free, fun and informative. See my website for lots of App Inventor tips, including links to the free tutorials:
Hope this helps :)