Unsupported BB-Codes Not Updated During VW3 Import
When importing from VW3, ever since Beta 2, instances of ATTACH are not updated to use IMAGE/FILE. Instead the appropriate replacement is added to the end of the text. Also, instances of CATEGORY are stripped from the page-text without adding the page to the category.
Fixed in the next release. Unfortunately, for affected pages imported during Beta 2-4 this information is unrecoverable, unless it is feasible for the admin to import clean from a backup.