If your voiceover in the rendered video is not the same as the preview, it might be this:

http://help.videoscribe.co/support/discussions/topics/11000001170/page/2?url_locale=

If you want the best results, it may be a good idea to record your voiceover first in another program and save it as an mp3. Then import it into videoscribe and build your project to match the voiceover.

If you think there might be issues with your project that cause it to render unusually slowly, there are some TIPS to fix or avoid rendering problems, crashing, etc.