Not a problem with the catalog, but with the file system on the drive. It's Windows NTFS and while Macs can read it, they cannot write to such drives without extra help due to the security stuff and permissions. You will have to think of something else like storing your stuff on a NAS so it is accessed via networking protocols, not native file handling or you have to buy a suitable system extension like NTFSforMac. Conversely, the same would be true if your disk was Mac HFS formatted and you wanted to access it from Windows. C'est la vie, chéri...
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