What version of Videopad is being used? Try the latest. For licensed users upgrades are free for up to six months from purchase date. After that, VP will continue to fully function but a fee will be required in order to register the newest. Retain your old install file and registration info.
Try exporting at a lower resolution. What are the export settings. How long is the project, how many tracks, and what's the resolution of the bulk of the source files?
If you share your project someone will check it out. This is easy, takes little time and can be private. Follow these instructions...
1. 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.
2. Locate the saved, numbered folder and upload it to a free server - Google Drive, MS OneDrive, etc.* (Don't upload the export or just the VPJ file.)
3. Get a shared, public link. If using Google Drive click SHARE. Click the blue "Change to anyone with the link." Then click on COPY LINK.
4. Paste that link here, or click the folder, above top-right in this forum, and message it to me. This is private and 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.