This happens in both Ti Studio and AppC Studio from latest GA to the nightly (current nightly: 220.127.116.11304292203).
1. Create a new mobile project
2. Make sure the location is not the default location
3. ERROR - http://www.screencast.com/t/2bBWaHAMWa2Z
Note that this happens to me when trying an Alloy project and non-alloy project.