Have been working on a manuscript but one of the files does not open anymore, it will not open in krita or gwenview with both giving errors. The error on Krita is
"Reason: Not a valid Calligra file: /Manuscript/13-14.kra" (Krita version 2.9.0 on Linux Mint)
The size of the file is about 30MB so the information is still all there, just not sure why the file is like this, all other files open fine with both programs.
Is there a way to repair the file? Spent 2 days working on the pages so hoping to fix this somehow T_T.

Try with a zip repair tool: if that doesn't work, you might have an autosave file that works, hopefully. If it still unzips but doesn't load, send it to boud@valdyas.org, and I'll look at it when I get back from LA.

Thank you very much, changed the .kra file to .zip and was able to extract the full image .png file. A few of the layer files seemed to have been corrupted somehow but thankfully the pages were already completed. Now the manuscript can be sent in thank you so much ^^.