What do you mean by not using L1? I thought that L1 is a specific pointer to some free memory?

Indeed, that's why you can't use it this way. L1 is already defined. You can't do whatever→L1. But you can do {whatever}→L1 whatever→{L1}, or Copy([101010101010],L1,6).

Also, what is "°MyMap"?

Seen from the program editor "°MyMap" is the "°" character followed with the "M" character... etc.
Seen from your program once compiled, it's a number. You just gave that number the name "°MyMap" because it's much more convenient to use.
Seen from the Axe Parser, it is a preprocessor name that means a number, it'll have to be replaced with that number at the end.
Seen from you, it's the pointer to what's before the "→".

Also, what is "°MyMap"? I mean I'm aware I can name variable, but how would I define, for example, a portion of memory 16 bytes in size?

It depends on what you call define. You can "create" 5 bytes of memory but just writing [0000000000] or Data(0,0,0,0,0) or Buff(5). Then you need a pointer to that so you can use those bytes, so you'll write → followed with a pointer. Note that doing this always works if you are only reading bytes, but if you compile as an app, you won't be able to write back to those bytes.
Alternatively, you can just use existing memory, like the area pointed by L1 or L2, or any free RAM area (or a non-free RAM area but maybe you won't be able to use your calculator afterwards).

From what I can see on the axe parser command list, Data () adds bytes to the program memory? What does that mean? What is program memory in this case?

Your program is just a bunch of bytes. Some of them are commands, some others are data, but it's just a pack of bytes. Data just adds some bytes in your program that you'll use as data. But if you mess up severely, you might be able to read or write data in the middle of your code and execute your data as if it was code

It's nearly as simple as that. Just don't put →L1 since this pointer is already used, but something else like →°MyMap. Then you can do {A+°MyMap} the same way you would do {A+L1}

It is as simple as that. Square brackets take hex. If you want decimal values you can use data().

You can also have binary values using Data() by putting a π (pi) in front of your values

Wat ? Did you mean "matref" ?

There is also Token that can generate pics, right? That said, it's for windows so unless you got a laptop it isn't as portable as the real calc.

Well I use a laptop in the train. And wow, thank you for telling me that because I actually found out now that TokenIDE can import images and convert them into hex

The problem with SourceCoder is that it is online. I can't use it when I am in a train.

And your post absolutely doesn't answer the question because you say "put [HEXCODE] then use Bitmap", but the question was "how to get the hex code other than converting byte per byte ?"

*Vim
 
More seriously, the only reasons I use Vim is that I don't like to have several windows opened (so I like to save one window by having both the terminal and vim at the same place) and Vim can run through ssh without -X. Other than that, Emacs is surely fine and surely has as many features as Vim.

Anyway, great idea of a project
And I like the fact it is not a standalone compiler in fact. This way, even if you stop updating it, it keeps working with newer Axe versions as long as they are on Wabbitemu

Just a question: is it fast ? I mean, faster than drag and dropping then compiling in Wabbitemu at speed 400% ?