EDIT: Was beat to it, dang >__< I guess that's what happens when you leave to do something and don't refresh your browser when you come back.
When it comes to ndless and ndless programs, they should run the same on both the CAS and non-CAS TI-Nspires, so that is a moot point.
First, find out what version of the OS you have (home->Settings and Status->4:Status... then look next to "Version:" near the top). This will determine if you need to update or not. Because 2.1.0.631 overclocks your processor, you should update to that version, so download version 2.1.0.631 of the OS at the TI website (there is one for CAS and one for non-CAS; download the non-CAS one and see if that works first).
For installing ndless, pop over to the
ndless beta thread and download the latest beta version (can be found at page 5). Next, get the TI-Nspire Link Software from the TI website and link up your calc to the computer (NOTE: Do NOT update your calculator under any circumstances using the autoupdater; if you update to OS 3.0 on accident, you will ruin all your chances of getting games or using ndless at all for a while). If your OS needs to be updated, do it the manual way: on the top of the Link Software, under Tools->Install OS, then browse for the .tno file for the OS.
Now you are ready to install. Extract the ndless .zip file somewhere on your computer and navigate there in the Link Software's file browser. In the calcbin, there should be three installers and an ndless_resources file. Drag/drop the 2.1.0 installer and resources file to somewhere on your calculator that is NOT MyLib (create a new file) and then copy over Particles.
Once the transfer finishes, unplug your calc from the computer and click on the ndless installer. If everything went smoothly it should say something like "Ndless installed!" and there should be a dotted line near the bottom of your screen; if it crashes, pull a battery.
Lastly, run Particles. If it boots up and runs, then that will also tell you ndless was installed correctly. If it doesn't work, report back here.
Note that ndless will not break the normal functions of your calculator and since it is cleared every time the RAM is cleared, you will need to re-install it every time you see the "Loading Operating System" screen.
