I've been messing around with the illustrated poses that our good Sepheyer kindly contributed some time ago (see post #240, page 12). At first, I though they were just pictures because their .png extension (I was very clever and knew that poses files bear a .dat extension), but yesterday I happen to move them on to the poses folder and surprisingly (for me) they works as fine as the original poses files.
I continued messing around and get to know that the .dat poses files are actually .png files, like .zipmod files are actually .zip files, but unlike them, you can change the extension and they continue working the same.
The same? No, better! With .png extension you can store them elsewhere and just drag and drop the pose file into Studio... and the selected character will inmediately adopt that pose. This is quite useful because you can see the .png files as thumbnails in your favourite viewer and drag and drop them from there. (You can't do that with .dat extension)
However, if you just change the extension of an existing pose file, the file will contain the pose data, but not a picture (it is easy to see if you look at the file size) so I wonder how could Hellborn (the author of the mentioned poses) make it? Maybe with an external program... but how?