thank you so much! I uploaded a new version that allows you to skip four levels, and changed the code limits on a few sigma levels, so hopefully that helps. also, clicking help at the bottom sometimes gives a hint, even on the later levels.
I could spoiler some things, but I don't want to ruin it. suffice to say that the [end] and [goto] commands are very powerful, especially in optimization. If you hit an extra [end], it functions like a [stop].
Agree. But still i like to test it.