The new version brings in full functionality, including the thumbnails display for all versions of Mac OS X – Mountain Lion, Lion and Snow Leopard.
Note that prior installing PSM on Mac OS X you have to install [free] ImageMagick.

If you have ImageMagick installed but PSM still can not show any thumbnail, do the follow:
1. Exit PSM if you run it

2.  Open a terminal window

3. In the terminal, type in

which convert

if you got ImageMagick properly installed you should see something like

/opt/local/bin/convert

in the response.

4. Copy the path to ‘convert’ to the clipboard, including the trailing slash (i.e. in the above case copy ‘/opt/local/bin/’)

5. In any text editor open the following file:

~/Library/ProStockMaster/ProStockMaster.properties

6. find a line showing

im_path=<some-path>

and replace <some-path> with the path to ‘convert’ you saved on clipboard (e.g. /opt/local/bin/)

Verify trailing slash in in place.

7. Start PSM and check the thumbnails

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