O MY GOD this works
If you have photoshop, you can open up DDS files directly. You don't have to use DXTbmp. This might not work unless you have a NVIDIA plugin, but I 'm pretty sure.
Flight Simulator and other chat
https://forums.simviation.com/phpBB3/
https://forums.simviation.com/phpBB3/viewtopic.php?f=21&t=65063
and who told you that dtxbmp is for working in dds format? and who told you that dtxbmp is for working in dds format?
neither photoshop although you can open things with it