Upgrading Slic3r and getting errors

I'm trying to upgrade the version of slic3r being used by RH, but it's kicking errors.  Basically, I've installed Slic3r in c:\program files\slic3r\ and have pointed RH to use the executable in that directory.  When I load an object and try to slice it, I get the error:

Generated G-Code Not Found
Expected Filename and Location
c:\Users/Shawn\AppData\Local\RepeltierHost\composition.gcode

And in the log at the bottom of RH, or tells me that there's an Invalid zero value for --default-acceleration when using other acceleration settings.

It seems to be loading my old Slic3r preferences fine (it pulls in my profiles), so I don't know what the problem is.