I want to add screenshots of this program I made. How could I go about doing that?

For that one, you will want to download WabbitEmu, put your calculator ROM on it, then you go from there. Otherwise, for now, I could try to get you a screeny (by the way, I saw that and liked it I even commented a page or so back about it)

What exactly are appvars and how do I use them?

Appvars are variables that can hold any kind of data in them and were originally intended for ASM programs and Apps. In Grammer, you can create an appvar of a given size and use it to store information. Currently, there is no way to resize an appvar, though. So if you want to create an appvar of 64 bytes called Data, you will want to use the Send( command:
Send(64,"UData→H
The "U" says it is an appvar (use E for a program, F for a protected program). by doing →H, the location of the data is stored to H for later use

I've been playing around with the particles function in Grammer, and just wanted to know if there was anything else I could do with it, like using the particle physics to make a Line Rider / Free Rider kind of game (acceleration/deceleration).

I haven't added in functionality like that, but from looking at your other program, I would suggest trying something like this:
Test the pixel underneath the front of the sled and the spot ahead of it. Also have a variable holding the acceleration.  If the pixel ahead is higher, decrease acceleration by 1. If it is lower, increase the acceleration. Also check the pixel 2 pixels below the front of the sled. If that is also on, you are on an accelerating track, so automatically increase speed by 2.

Also note that once velocity becomes negative, the "front" of the sled and "back" of the sled can be reversed.

How can I generate a random number, like randInt( in BASIC?

In Grammer, you can use rand to generate a random number from 0 to 65535. However, I can add in the randInt( function if that makes life easier

In other news, Grammer has been successfully put into App form ! Right now I am working on the menu to select a program to run. Once that is finished, I will release Grammer 2.0!

So I have a question: I am using Brass, so how do I change the name it assigns my app?

Sorry folks, I hope nobody used the Pt-On( command! I left in some debugging code that will cause it to freeze in an infinite loop. I just uploaded the correct version. Here is the link: http://www.omnimaga.org/index.php?action=dlattach;topic=9067.0;attach=9954

You do it the same way you write data to a program All I did was make the program in the program editor and then I used Calcsys to change it to an appvar. But if you want an example, here is how to make an appvar that has two screen buffers:
Send(768*2,"UBUF→H
+768→I
Now H points to one buffer and G points to the other And from there, you can use some Fill( commands to copy the graph screen to a buffer and then you won't need to mess up the graph screen!

O>O I just realised I can add the commands DelVar, Archive , and Unarchive

mmm, maybe I wonder how Axe changes it tokens... ?

Sorreeee I tried to keep ReCode and Grammer pretty similar (just safer and more likely to work as expected in Grammer). Though Grammer has had a lot more polishing and a lot more features...

Awesome and good luck! Feel free to ask questions

But that would mean that keys don't register if something like headphones are in the I/O port ...

Hmm, now there is an interesting idea... I haven't programmed that in, but I think I could make some special key combinations register... So the diagonal directions are a given, but what should I do for 16 and 24?