single space Pages becomes space-and-a-half in Word

I've adjusted the Text Inspector when composing my Pages documets so that the space betweeen lines of text will be displayed as single-spaced. When I Export and convert the document I prepared to become a Word document, the person who recieves my e-mailed manuscript sees it (on their PC with Microsoft Word) as having space and a half between lines.

How to keep the single-spaced Pages document single-spaced, when it is changed into a Word document is the question.

I've read on other posts here to adjust the before and after paragraphs settings to fix this. But how? Can't I have it be double-spaced between paragraphs while keeping the text single spaced between lines within the paragraph?

(In Pages, the document looks fine, it's that in the translation from one format to the other that the changes take place.)

I have even noticed that the font can also undergo undesirable changes in this translation preocess. How is it for example possible that Apple's Pages Helvetica looks quite different in apearance from a Microsoft Word Helvetica? Isn't a font a design that transcends company settings?

Thanks in advance for helping me sort through this.