I continue to be unimpressed. I took the advice offered here and tried a much smaller file - a 12 megapixel Canon RAW. Half an hour.
And why are the output files so huge? The input RAW was 19 megabytes, the output TIFF was 438 MB (with a 150% uprez setting).
Then there's the matter of color. The output is much duller than the input - using the Adobe RGB color space. See below, the original on top and the Gigapixel output below.
Don't use a raw file! This introduces a lot of variables not the least of which is using AIG (A.I. Gigapixel) as a raw converter. Your problem may be that AIG is hanging doing the raw conversion.
Convert whatever raw file into something that is known. Known color space, known number of pixels, etc. Save it as (an example) a four megapixel sRGB TIFF file and then run that through AIG. If the color is OK, then try it as a four megapixel Adobe RGB file. See if the color is correct.
If the color is OK, then try larger files and see what the conversion times are.
Note that I suggested 2X scaling. AIG only scales 2X, 4X, and 6X natively. For any other scaling (150%) it rounds it up to the closest native scaling (2X) and then downsamples it. This is another variable.
AIG is very GPU intensive. This is why I asked what graphic card you are using. If the graphic card's GPU is minimal then processing time will be long. I added a $500 Navidia 1070 Ti card to my computer solely to run AIG. (Early versions of AIG wouldn't run at all unless you had a supported GPU. The most recent versions will run if you don't have a supported GPU, but more slowly. Or maybe your GPU is unsupported and AIG is very slow trying to use it. Another variable.) If it still is very slow processing a small file, then switch off using the GPU in AIG.
The point of my suggestions is to get you to start with an small image file that has a reasonable conversion time (even with minimal GPU power). And known colors.
12 megapixels isn't "small" in AIG terms. a 2X conversion multiplies the input number of pixels by four (etc.) So a 12 megapixel input file will become a 48 megapixel output file.
AIG is New Technology that has stringent hardware requirements. It also does something that no existing program does (creating new detail from scratch.) Whether or not this is worth the stringent hardware requirement is up to you.