Here is something that may be useful to you. The attached will open a .abr file as layers in Gimp. Works on many (but not all) .abr files.
Put the 2 files in your plug-ins folder. Then use File > Open to open the .abr
EDIT: Gimp opens the .abr as a grayscale image and each layer is on a white background.
Put the 2 files in your plug-ins folder. Then use File > Open to open the .abr
EDIT: Gimp opens the .abr as a grayscale image and each layer is on a white background.