The projection images not AFNI datasets. They are single slice images; since you used the "-nsize" option, they are probably stored in the GE I.* format. To view them, you can try a command like
afni -im prog.*
The little known "afni -im" option (which is detailed in the output of "afni -help") lets you simply view images using AFNI, rather than datasets. Use the Sagittal image viewer to look at the images. The only constraint is that the images must be stored with the same NX x NY grid size.
To get statistics on an image, try a command like
imstat prog.*
bob cox
