If you are trying to convert your OLM files into multiple file formats then I will personally suggest you use the MacSonik Mac OLM Converter. It converts OLM files into multiple file formats like PDF, PST, EML, MSG, TXT, HTML, MBOX, DOC, CSV, and more. It helps to Remove similar or duplicate email items and one of the best features of this tool is that you can backup and migrate your Mac OLM files without attachments. It excludes email attachments from the conversion/migration procedure without data loss.