You're right... partially
On second screenshot, there is really a scaling effect, despite it's in 640px wide. I write few months ago an article on DKNET for
running DK over DosBOX for MacOSX. Inside DOSBOX.CONF, I use "
scaler=advmame3x" parameter : "smooths corners and removes jaggies from diagonal lines" (see
here for more infos). This parameter is very closer to "hq2x | hq3x" rendering, also supported by DosBOX.
But if hq2x | hq3x | hq4x rendering aren't very usefull for KeeperFX, may be some
other ones exists for enhancing gfx without having to re-create new sprites & textures, nope ?