Hi, sure I’d love to help. First the standard question. Have you tried re-downloading the pack and opening the affected file from that? Potentially the file might have gotten corrupted during the download, its odd but it can happen.
If the files are still crashing, can you let me know which file(s) are affected by that? I have not encountered something like that myself until now, but I would love to double check those files. I am also looking into providing the .fbx or .obj files with the next update to hopefully prevent that in the future.