If the software is freezing when you are editing videos or rendering, the first thing you should do is reset the program to its default settings. To do this, follow these steps:

1. Open the program and hold down Ctrl+Shift until the program has finished starting. 
2. You should get the following message: "Do you want to reset all preferences to default values?". 
3. Select "Delete all cached application data" and click "Yes".

Other things you can do to resolve this issue:

• If you are using the latest version of Movie Studio or Vegas, disable GPU acceleration by going to "Options" > "Preferences" > "Video" (tab). Exit the program and open it again.
• Make sure the program is using "CPU only Encoding" to encode AVC templates.
• Disable all startup applications in Windows and restart your computer. Click the following link for instructions on how to perform a clean boot in windows. 
• To free up resources, remove any multimedia objects from your project which are not being used. To do this, open the "Project Media" tab and click the button with the lightning bolt on it. In Movie Studio Platinum 13, this feature is located under "Tools" > "Clean Project Media".
• If possible, chop your project up into smaller sub-projects and save each of them by going to "File" > "Save as".
  If needed, reimport each sub-project into a new Master project to recombine them.
• Do not make changes to the rendering templates. If you are using custom rendering settings, try rendering your project instead with one of the included rendering templates.
• Before doing this, place all your source files in the same folder and import them from there into your project.
• Create an exception in your antivirus program for the software's .exe file.