glowscript | Graphics library

I used a youtube video for the basis of my code and adjusted it to include classes and object. The original code from the video works perfectly. My version of the code returns a black screen and even when trying to fix it the most luck I get is the two objects displaying without moving. I've also tried running it on glowscript IDE and winpython. Thanks to anyone who can help!

I try to understand this code and I actually understood the whole thing except these 2 line:

I'm implementing a solar system with VPython in GlowScript. Now I have received this error when running: Error cannot add scalar and a vector. I think I've done all correctly. Do I have to change something with the pos. ?

Here is the code:

When I run this code I get an error "Error: Property 'pos' must be a vector." Do I have to write another vector somewhere? Because I wrote vector at

glowscript.org is a Python-based GAE that stores user-written scripts in a datastore. How would I program in the Python server and/or JavaScript client a button that lets the user download to the user's Download directory one or more of the user's scripts? All I was able to find in my searching seemed to be oriented to me downloading the datastore from a command line, which seems unrelated to my case.

In working on a simple program to simulate and visualize crystal vibrations and molecular dynamics.

I'm not a very experienced programmer so I looked for an easy-to-use tool to work with, and I found that vpython (now GlowScript apparently) is simple enough and gives good results. But it lacks some basic functions like panning the scene, which breaks the deal for me.

What other tools are there out there, with reasonable learning curves (not raw opengl), can I use to create 3D simulations? (preferably within the python environment)

Here - An example in vpython similar to what I want to achieve