The VPJ file that you linked is an instructional file that tells the project what to do. In itself, it's usually not helpful. What version of Videopad is being used? Look at the bottom-left corner of the window. Test this Windows release. You can always revert.
Search for an autosave VPJ file in this path... C:\Users\[Your username]\AppData\Roaming\NCH Software\VideoPad\ autosave.vpj. Search the PC for others.
If no VPJ will load, zip all the source files, then upload the zipped folder to a free server, such as Google Drive or MS OneDrive, right-click the link and Share or Copy. Copy the result and paste it here. Someone will be glad to help.
When using Google Drive, right-click the file, then click SHARE | SHARE and change "restricted" to "anyone with link can view.
If the project will load onto the timeline, do this instead of the above. Don't skip any 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.
Zip the folder --- It will be numbered. In Windows right-click on it and Send To > Compressed (zipped) folder.
Upload --- Use a free server - Google Drive, MS OneDrive, etc. - to upload the zipped folder. When it completes...
Get link --- Right-click the file and click SHARE. If using Google, right-click the file, click SHARE | SHARE. Change "restricted" to "anyone ... can view"
Share --- Click COPY LINK or OK | DONE. Paste that link here. Or request first that it be made private.
Always Save Project File AS routinely, giving it a unique # or name, so as not to overwrite prior saves. Using Save Project Files (no AS) will overwrite. From the HOME tab, the AS choice is available by clicking the caret to the right of the Save Project button on the toolbar. That way you're protected, and shouldn't lose anything.