This is a command line utility to help you transfer psd files and convert them to gimp files. Layering will not be affected.
PSD/PSB Converter to Gimp XCF layered formatStandalone command-line (Terminal) tool to convert Photoshop layered PSD files into Gimp's XCF (v1) format. Also may help recover damaged PSD files.
Very fast and reliable conversion (e.g. less than 2 seconds to convert a 40MB PSD to compressed XCF, on a 2004 model PC). Note: Currently converts image layers only.
acheteeeteeep://telegraphics.com.au/sw/product/psd2xcf