Open files from SD card e.g. Contents\registered files

[Feathered-Serpent]

Heya,

I wondered, if one can open files from the SD card with nstool. There are quite some big ones, for example:

(Note that the folder has .nca at the end of the name, the files are without extension)

But when I try to use nstool on one, it just says [nstool::SettingsInitializer ERROR] Input file type was undetermined. and if I try to use -t nca nothing happens at all, no message, not even another error message.