If you'd like, I can give you specific steps for (like Mari or 3D Coat) or help you find licensing details for a specific project.
Open the Alpha palette, click Import , and select your desired files. Download File 100-ultimate-stylized-alpha-pack-...
Copy the .psd or .tif files into your ZBrush installation folder, typically: C:\Program Files\Pixologic\ZBrush [Version]\ZAlphas . They will then appear in the Lightbox under the Alphas tab. 2. Substance Painter If you'd like, I can give you specific