rename files GUI

A gui utility to rename file(s) in a directory. This gui contains
two list box:
on the lefthand side is the contents of the current directory,
on the righthand side are the files selected for renaming
a button '>' is used to select the files
a button 'Rename' start the actual renaming process
a button 'dir' to select the work directory
a thick box to specify wether to rename read only files or not
the user, in order to rename files, must
1) select the working directory with the button 'dir'
2) select the file(s) on the righthand side window with mouse and 'ctrl'
to make multiple selaction of non-adiacent files
3) press the putton '>' to select the files and choose the new name:
the character that cannot be changed in multiple selection are
represented by '?' (question marks), the remaining character can be
changed or removed; characters can be also added, thus the resulting
filename(s) will become longer.
4) press the button 'Rename' to start the renaming. A progress bar shows
the progress of the operation.
Version 2
Is now possible to change the extention in multiple selections:
At the point 3) write the new name starting with a dot.
The first three characters after the dot will be used as the new
extention. Otherwise, no matter the number of selected files, using
the expresssion *.ext1 *.ext2