Hi, this short critique is for the workshop:
You correctly used the slug-line to introduce the setting. Your margins look good. Characters names are in all caps when introduced and when speaking, which is good.
As far as centering the dialogue goes: I'm not sure what software you used, but for centering the dialogue properly in Microsoft Word you can select the dialogue text, open the paragraph tool, and create a hanging indent to keep it from spreading all the way across the page.
I hope this is useful to you!