Actually, the program is probably going to read the images OK, but you have to let the error messages run free. The reasons for this behavior are that I changed the order in which the program tries different file formats. Most formats come with some marker near the start of the file indicating their contents, but DICOM does not require such a marker. So if the program can't guess the filetype from its filename, then it tries DICOM - but your files aren't DICOM, so then the DICOM reading functions (adapted from the RSNA's sample programs) complain. After DICOM fails, then at the last gasp the program tries the simplest binary formats, including the GE IMGF format and the various headerless formats AFNI knows about - one of which I guess fits your data.
I don't know an easy solution for you, at least at the moment. Do you get the data read OK if you just let the messages roll on?
bob cox