I am running the tool in a windows 8 command prompt and after scanning or building it does not return to the prompt.

I've also noticed that one should probably not change the background color of the command window to white since the tool seems to only output white text. Also, after I ctrl-C in order to return to a prompt the text color has been changed to red.

Am I missing something here?

We have detected some scenarios where buildtoold.exe never returns. Probably you had xamlplayer.exe running or another instance of buildtool.exe in parallel (could you confirm this please?)

This bug and the other ones you are describing will be fixed in the next release.

Thanks for reporting!