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Hi Claire,

Yes, CONVERTPSTYLES is not available on Mac, but you can try one of the following :
- create new CTB based drawing, open your existing STB based drawing, select everything in it, copy to clipboard, then paste to the new drawing you created in the first step, save new drawing.
Or
- create new CTB based drawing, then use INSERT command to insert the whole old STB based drawing - use Browse button to navigate to the old drawing). Don't forget to check mark "Explode Block" option before clicking on Insert button.

Maxim