You are welcome to use CrystalDiffract-generated media (graphics, data, etc.) in any of your publications: there is no separate licensing agreement or fee for this. However, we do require you to acknowledge the use of this software. A suitable example would be:
Generated using CrystalDiffract®: a powder diffraction program for Mac and Windows. CrystalMaker Software Ltd, Oxford, England (www.crystalmaker.com)
If space is at a premium, you can just list the application name, company name and web address. Please remember to include the registered trademark symbol ("®") after the application name: this is important, for legal reasons.