Endless problems in viewing classical trajectory

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I simply wish to view the trajectory of an md optimization or dynamics run.

input for previously prepared system:

start mypdb
memory total 1000 mb
 system mypdb
 record coord 1
task md dynamics
   system mypdb
   reference mypdb.rst
   file mypdb.trj
   copy mypdb.dcd
   copy mypdb.crd
task analysis

MD completes without error, and 1000 frames are allegedly written to the dcd and crd files.

First attempt:
VMD. After successfully loading the original pdb file, I try to load the crd or dcd file per this link's instructions:
and no dice. crd gives an appropriate number of available frames, but there is clearly something wrong because the "trajectory" just flashes atoms and bonds around the screen. Perhaps I needed a proper "psf" file to start, which I am unsure how to generate

Second attempt:
pymol. Loading the .top (topology) file gives the following message:
ObjectMolecule: Assuming this is an Amber6 topology file.
TOPStrToCoordSet-Error: Error reading counts lines

following that, I load the .trj file as per pymol documentation instructions (load_traj) and receive the following error:
 ObjMolLoadTRJFile-Error: Failed to read expected coordinate value.
  This traj. does not match the loaded parameter/topology file.
  Likely cause: either the atom count or the periodic box settings
  are inconsistent between the two files.

Last attempt:
I understand that I may write individual frames to disk using the "write" command within an analysis block.
This would be acceptable, as I may catenate the files after. however I am new to nwchem and do not know how to write a loop to make this happen with all frames. This is my attempt:

  num = 1
  while (num <= 10):
         system mypdb
         reference mypdb.rst
         file mypdb.trj
         write %d mypdb_%d_coord.xyz
    ''' % (num, num))
    num += 1
task python
task analysis

Unfortunately, it only pays attention to the very last analysis block from the python loop, and I can't figure out how to run "task analysis" between each python while loop because input_parse() ignores task commands.

Any help is greatly appreciated, because I feel stuck and having trouble finding a solution online.


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