The conversion should not get stuck in the process, something is probably preventing/blocking QS for completing the conversion. You need to eliminate the block in order to complete the conversion.
Have you done the proper preparation as mentioned in thispage: Preparing a conversion project?
In addition? Make sure you have enough disk space and other system resources to handle the QV app and the new QS app. Is the app size very large, then it might help to reduce the data in the qvw before making an attempt.
