Is there a way within the gimprc or gimp pluginrc file to load a file extension (eg. cr, cr2, nef, dng, ...) as a default UFRAW file type?

In other words, I have *.nef files and Gimp enjoys choosing to only open the *.nef file's thumbnail as a TIFF file, ignoring the remainder of the contents of the *.nef file, which further includes an embedded JPEG and RAW NEF image file data.

Some searching the Internet led me to the following: gimprc: (gap-load-ufraw-nef yes)
NOTE: Only for gimp-gap plugin usage

Also I see within the gimp pluginrc file the ufraw file extensions section, also listing some additional data types that might be prioritizing the file type during importing.

The specific procedure for specifying the file type is: file-ufraw-load
Unfortunately, there are really no examples on the Internet (that I can find) showing users how to take explicit control of this import process with specifying the file type by file extensions, except via the O/S level.

Going off on a slight tangent, I can see where a sub-menu option should be within the load menu upon selecting and *.nef file (or similar RAW image file containing multiple images), where the user should be able to check/tick the images to open (eg. Thumbnail image, JPEG image, RAW image, ...) and make those chosen options default until modified later again.

I know, you'll be awaiting my patch submittal. ;-)

I am assuming you are using GIMP 2.8 series and have UFRaw properly installed? If so, if you click on the automatic file type detection, you'll
see that these extensions are already associated with raw (as in ufraw).

However, some of the time, you will note that GIMP is unable to pass the
file to UFRaw and insists on opening the embedded thumbnail as a TIFF file
since NEF is based on the TIFF format.

If you select raw (with all the extensions on the right side) and then try
to open your NEF files, do they open correctly?

Well, the question is, is how to set UFRAW for *.nef, *.raw, ... as the default editor without having to additionally manually navigate through the list specifying the file type. (Also note, I believe there are two *.raw filetypes in my list, with UFRAW type being listed all the way at the bottom.)

No problems once file type UFRAW is manually selected, the process just gets extremely tiring to click through. Doing some research on the .gimprc and gimp pluginrc, it certainly looks as either the a default type can be specific within either gimprc or gimp pluginrc, rather than having to confirm each time or inadvertently forgetting and just getting the thumbnail. (Tiring...)

Maybe I should also search through the Book of Gimp to see if this is listed there, but I don't think so. Most the book probably covers is (thankfully) scripting.

After much time spent with UFRAW and dcraw, starting to invest some time into learning RawTherapee. Looks like lately a majority have migrated towards RawTherapee.

Sorry, I did not proof read my last very well.