Slic3r won't let me have more than 0 extruders

When I downloaded Repetier, Slic3r's default number of extruders was at 0.  When I clicked the arrow to increase it to 1, the program terminated and the log read "<Slic3r> Use of an uninitialized value in the subroutine entry at C:/PROGRA~1/Repetier-Host/Slic3r/lib/std/Slic3r/GUI/OptionsGroup.pm line 166."  I then tried to change it to 4 so I could then decrease it to 1 but whenever I try to change it by typing another number in, Slic3r crashes.  Any idea what I can do?