A full "collection pack" should be several gigabytes. If the file is only a few megabytes, it is likely a placeholder or a malicious link.
Look for comments or "upvotes" from other users who have successfully extracted the files. Managing Your Comic Library fulldownloadlustomiccomicscollectionpack checked link
Apps like CDisplayEx (Windows), Panels (iOS), or Moon+ Reader (Android) offer the best experience. A full "collection pack" should be several gigabytes