hi
the largest size a thumbnail can be is 512 x 384 pixels this is set from the thumbnails and proxies section of the preferences see below

this is a global setting so if you want some thumbnails to be of a different size change this setting then create or recreate thumbnails ( media menu > build thumbnails ) then set it back to your preferred option for other files.
CatDv can open files in the default file viewer , this can be enabled in the Preferences under Advanced media handling check the Playing non media files Launch in external application option
see below

with this selected double clicking on a file will open it in the default application
eg for a *.psd catdv would launch and open photoshop *.doc Microsoft word etc etc
I hope this helps Catdv become more useful for you
thanks dougal
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