To open an OBJ file in ZBrush 4R6 2014, follow these steps:

1. Launch ZBrush 4R6 2014 on your computer.

2. Navigate to the Tool palette and click on the Import button.

3. In the file browser window, locate the OBJ file you want to open and select it.

4. Click on the Open button to import the OBJ file into ZBrush 4R6 2014.

5. Once the OBJ file is imported, it will be loaded as a new tool in the Tool palette.

6. You can now start working on the imported OBJ file, sculpting, painting, and modifying it as needed.

It's important to note that ZBrush 4R6 2014 has specific requirements for OBJ files. Make sure that your OBJ file meets the following criteria:

- The OBJ file should be properly UV-mapped for textures and materials to display correctly in ZBrush.

- ZBrush 4R6 2014 supports OBJ files with multiple subdivision levels, allowing you to sculpt and modify the mesh at different resolutions.

- Ensure that the OBJ file does not have any errors or corrupted geometry that could cause issues during import.

By following these steps and considering the file requirements, you can successfully open and work with an OBJ file in ZBrush 4R6 2014. This allows you to leverage ZBrush's powerful sculpting and painting tools to enhance and modify your 3D models for various creative projects.