Has anyone tried and had any success using klayout to convert from Cadence layout.oa to GDS?

Doesnt cadence already have a stream out option to convert oa files to gds

It does. You have to have a Cadence license and Cadence tool to do so, though. 😁

Ahh gotcha 😅

You can try https://layouteditor.com/

Thanks @Andreas Krinke! I'll give it a shot.