In brief you have a few options.
(1) The black and gray rectangles you
see can be removed in illustrator,
they are in layers over the actual figure. Ungroup everything and delete those rectangles, you should see normal images underneath
(2) The "batch"
screenshot option does not suffer from this, you can write a small batch
script to get the screenshot then run it from the file menu. See
http://www.broadinstitute.org/igv/PortCommands. The behavior here is somewhat different, the screenshot will include much more in the way of imagery.
(3) I've opened these files with Inkscape and they look fine without adjustment.