Can't save a document opened into Zoho Writer from the leads tab in CRM

Can't save a document opened into Zoho Writer from the leads tab in CRM

When on the leads tab of CRM, if I click on an attachment a dropdown menu displays giving me two options:
1. Download
2. View in Zoho Writer

when I click on #2, the document (no matter what format, Word, Google doc or Zoho doc) opens into Zoho Writer. I can edit the document, but when I want to save it, the save button is grayed out. How can I save the document? Do I need to upgrade? I am currently on the free trail period of the professional edition.

txs in advance

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