Any number of files on Karst can be compressed into a single (large) file using the following linux command and the compressed file can then be easily transferred to another computer:
$ tar -czvf compressed_file_name image_files
$ tar -czvf myImages.tgz *.png
$ tar -czv -f originalData.tgz *dm3
$ tar -c -z -v -f someImages.tgz image1.dm3 image2.png image3.jpg etc.
$ tar -czvf myFiles.tgz directory1/ directory2/
Note: among the -czvf "flags" ->
c == create z == compresss ("zip")
v == verbose (show what is happening)
f == output file name (and MUST immediately precede the compressed_file_name)
Compressed files made this way can be un-compressed using the same tar command ("tar -xzvf compressed_file_name" where the "x" indicates "extract") on any Unix/Linux computer and using normal file compression utilities such as WinZip, 7-Zip and WinRAR (Windows machines) or Stuffit Expander and the tar command from a terminal window (Macs).
NOTE: You will need to use some sort of secure FTP client such as PuTTY's psftp or WinSCP to transfer compressed files from Karst to a Windows machine (and you will in fact need to initiate this transfer process from the Windows machine and not from Karst). Macintosh and Unix/Linux machines should have sftp available on the command line and it should be possible to initiate the transfer either from Karst or the other machine.