ncdf2vdf does nothing

I am using the latest Vapor code (2.6.0.RC0). I create a bunch of netcdf4 files that look like the following:

(ncdump -c output):

netcdf fs8.07800.000000 {
dimensions:
xh = 601 ;
yh = 701 ;
zh = 201 ;
xf = 601 ;
yf = 701 ;
zf = 201 ;
time = UNLIMITED ; // (1 currently)
variables:
float xh(xh) ;
xh:units = "km" ;
float yh(yh) ;
yh:units = "km" ;
float zh(zh) ;
zh:units = "km" ;
float xf(xf) ;
xf:units = "km" ;
float yf(yf) ;
yf:units = "km" ;
float zf(zf) ;
zf:units = "km" ;
double time ;
time:units = "s" ;
int X0 ;
int Y0 ;
int X1 ;
int Y1 ;
int Z0 ;
int Z1 ;
float uinterp(time, zh, yh, xh) ;
float vinterp(time, zh, yh, xh) ;
float winterp(time, zh, yh, xh) ;
float xvort(time, zh, yh, xh) ;
float yvort(time, zh, yh, xh) ;
float zvort(time, zh, yh, xh) ;
float hvort(time, zh, yh, xh) ;
float vortmag(time, zh, yh, xh) ;
float streamvort(time, zh, yh, xh) ;
float qc(time, zh, yh, xh) ;
float qr(time, zh, yh, xh) ;
float qg(time, zh, yh, xh) ;
float dbz(time, zh, yh, xh) ;
float thrhopert(time, zh, yh, xh) ;
float prespert(time, zh, yh, xh) ;

I create a vdf file as such:

vdfcreate -vdc2 -dimension ${nx}x${ny}x${nz} -extents ${gx0}:${gy0}:${gz0}:${gx1}:${gy1}:${gz1} \
-startt $t0 -deltat $dt -numts $numtimes -vars3d $varlist \
-level 2 ${base}-${vdfs}.vdf

(this is from a script).

The vdf file looks reasonable.

Then, following the instructions from the man page, I try all sorts of things to create the vdf files and they all fail silently, doing nothing.

For instance:

ncdf2vdf -timedims time -timevar times nc/*.nc fs8-fromscratch8.vdf

It will return in about 5 seconds and nothing happens - no VDC files are created, nothing is output.

I ran strace on the command and it is indeed reading data from the netCDF files.

I have tried many variations on the ncdf2vdf command and I always get no result.

Here is a link to my .vdf file if it helps:

http://www.ssec.wisc.edu/~lorf/fs8-fromscratch8.vdf

Thanks,

Leigh