Changing the color of thangs is a bit tricky, but in the case of a gem, you can add the display.Colored component, and configure it like:
(You’ll have to play with the values a bit to find the right color.)
OR you could look in the thang list for the Heart Seed 
Usually a level will have a thang called a Referee that contains code on the misc.Referee component that does all the custom fun stuff for the level. If you see a level that does something you like… load it up in the editor and try looking in the referee code.
For example, the level backwoods-buddy has the referee listen for the pet speaking.[quote=“Hellenar, post:1, topic:11748”]
Finally, when the player opens the level and plays it, how do I input comments in the code to guide them through? I also want to add a “Hints” section.
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The sample code and comments for a level are on the Hero Placeholder thang in the programming.Programmable component under programmableMethods.plan.
Hints/Guides/Intro screens are in the Settings tab under Documentation.