What are your PC's specs: CPU/GPU/RAM?
Two things to try...
Install this release. It may or may not be the same as the one you're using now.
Under OPTIONS | ADVANCED, change the GPU processor item (at the bottom) to None (CPU only). Then restart Videopad. 
If these measures don't fix the issue, please take a few minutes to share the project. Someone will come up with a fix. Follow these steps...
Back up --- With your project on the timeline, click on MENU at the top-left. Click FILE|BACK UP PROJECT FILES TO FOLDER. Choose a folder and SELECT FOLDER.
Upload --- Use a free server - Google Drive, MS OneDrive, etc.* - to upload the saved, numbered FOLDER. Do NOT upload the individual VPJ or export file.
Get link --- Get a public link. If using Google Drive click GET SHAREABLE LINK. If necessary change "restricted" to "anyone with the link can view"
Share --- Click COPY LINK | DONE. Paste that link here, or click the folder at the top-right of this forum to message it privately to me. It won't be shared.
* Before uploading, right-click the folder, click PROPERTIES. Look at the File Size to confirm that it's not too big for the free space on the server.