I note that your content in both files have different style definitions for Normal AND they also have font overrides on this style. Your content in the ahm doc has a Normal style definition of Univers 12pt combined with a font override changing the typeface to Arial. Your content in the initial setup doc has a Normal style definition of Courier 10pt with a font override changing the typeface to Arial.
The problem you are encountering is a style issue. The two documents have different definitions for the style Normal. When you paste content formatted using this style from one document to the other then the pasted text adopts the style attributes in that location (other than the overridden attributes). This is usually a good thing as it allows you to put together more consistently formatted documents.
However, in your case this is not what you wanted. So you have two choices to resolve this and retain the fonts and sizes from the source document.
- Create a new style definition in the source (ahm) document and apply this style to the content there. If you use a style name that doesn't already exist in the target document then when you paste in the content, it will not change its appearance at all.
- Modify the style definition in the source document to match the style definition in the target document. Then format the text the way you want it to appear in both places. When you paste in the content that uses this matching style then it won't change its look.
Wendell's suggestion won't solve your font size change issue but it is one way to speed up retrieval of the letter content. I would also suggest you use a template for this work and include the possible letters as "autotext" entries in the template.