Unfortunately the dcraw (version 8.88) included in TVersity version 1.7.4, does not support the Canon 7D camera.
Pukkita's Digital Darkroom Corner has more recent builds of dcraw. There are actually two versions, and type which works on my system (the file dcrawMS.exe) still does not contain Canon 7D support.
Instead, I've got a version from LibRaw. This is not exactly the same. The file dcraw_emu.exe is mostly compatible - but does not support the -c option (which TVersity uses). This option is used to force output to stdout. I've modified dcraw.bat to handle this incompatibility:
@echo offOf course, once TVersity is updated, then this will no longer be necessary.
echo TVersity is converting a raw digital camera image ...
dcraw_emu.exe -w -h %1
move %1.ppm %2