Well, do you understand maya's node arhitecture?
Like I said you have description of all MEL commands in Mayas help file.
There you also have script examples for each syntax and meaning
of each flag!
Try:
window;
and see how can you create the window with buttons and commands assigned to the buttons!
I started by scripting costumUI...
In expression editor type:
polySphere.translateX=polyCube.rotateY //snytax is(object.attribute)
in that way you will connect nodes translateX attribute with othe node's rotateY attribute!
Just like any other program language,just like math, it takes some practice and time to get comfortable with!

So practice!
:attn: