That error comes up for one of two reasons:

1.) Items from the Data folder were installed in the wrong location.

2.) The file was missing from the original zip (the one you downloaded from Renderosity).

Look at the error message again. What path does it give you for the missing file? Check the product zip file and see if you can find it in that location… if not, you'll need to contact the vendor and let them know there's an issue.

If it is there, just move it to the right location in your data folder. That should solve the problem.