If you read on it says that MakeTNS is used to add this to binary files. So when you compile it calls MakeTNS and adds the header while changing it into a .tns file readable by the calculator.

I think you can also just add this asm(".string \"PRG\"\n"); to the top of your file just below the included headers as shown in the demo program.

OK, thanks! So, just to check:
If, then, function loops, while, for, that stuff is supported, but

Disp, PrintL, Print, Input-ish commands are not, as they're hardware specific.

Does that sound about right? Thanks for the help!

BTW, I started out just peeking at the common.h, and found something I thought was rather irritating. They only set black and white as color values beforehand, so I wrote in 16 new #define lines.

The original BLACK and WHITE commands are intact, so it should be 100% compatible with old stuff while making grayscale easier to write. I simply defined COLOR0 through COLORA for Black to White and gray in between.

Like so:
Original:
#define BLACK                   0x0
#define WHITE                   0xF
New, improved:
#define BLACK                   0x0
#define WHITE                   0xF
#define COLOR0               0x0
#define COLOR1               0x1
#define COLOR2               0x2
#define COLOR3               0x3
#define COLOR4               0x4
#define COLOR5               0x5
#define COLOR6               0x6
#define COLOR7               0x7
#define COLOR8               0x8
#define COLOR9               0x9
#define COLORA               0xA
#define COLORB               0xB
#define COLORC               0xC
#define COLORD               0xD
#define COLORE               0xE
#define COLORF               0xF

Like it?

that's true......how exactly are the nspire keys mapped? Are the alpha keys on a separate matrix, or is it just 5-key then 6-key then 5 again on the matrix?

Also, do you know anything about the keys at the top? how are their addresses configured, as well as the pad itself?