The macro you paid for seems overly complicated to arrive at that solution. You can get that kind of alignment two simpler ways without using a macro to add a special-sized space.

Method 1. Add a tab at the END of the paragraph and apply this paragraph alignment
Selection.ParagraphFormat.Alignment = wdAlignParagraphDistribute

This method is the one I recommend because the text can be edited freely without breaking the layout at any time. You can also apply it quickly to existing text with a style and a simple find/replace macro to make sure there is a tab at the end of every paragraph.

Method 2. There are special alignment tabs which can be inserted into a header/footer (only available via the Header/Footer tab on the ribbon) and then copy/pasted into the body of the document. One of these 'special' tabs allows you to centre the text. It could be used instead of the space shim that the addin placed in your sample doc. The benefit of this is that you don't need to calculate the size of that shim for every paragraph.

This second method is barely better than than the addin method since you still need to work out where the soft return goes and would need to fiddle a lot when the paragraph is subsequently edited to fix it up when line lengths change.

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Andrew Lockton
Chrysalis Design, Melbourne Australia