The OCR conversion option is not working for me. Does OCR only work for documents written in English?

Unfortunately, this is true.

OCR technology that we currently use in Able2Extract Professional can only convert scanned PDF files written in English. Other languages are presently not available for conversion of scanned PDFs. But if we ever release a multi-lingual version for OCR, we will certainly let you know.

This article refers to Able2Extract Professional.