Looks like there might be a problem for a few people who have updated to 0.315. If you can't load GrooveWalrus after updating, download http://turnip-town.googlecode.com/files/gw_0315_fix.zip and unzip and overwrite the gw.exe in your GrooveWalrus directory. Or, download the installer for 0.314, and update again (I put a new 0.315 update on the server).