i thought wally did.. ok.. try it this way..
open the original wad file..
then.. go to the top selection..
and click 'export image' or something close to it.. around there around the top bar
and save the image to your desktop as a .bmp or .jpg..
THEN.. reopen the image as a half-life image file
copy, and paste that into a 'new' halflife wad
see if that doesnt work
(but i dont use the new wally, i personally dont like it.. if you find a means of downloading an older version.. i know it has support for exactly what your trying to do)