The excerpt include is unable to find pages that are named with certain special characters. For example ":".

Replication Steps:
1)Create a page with a special character of ":" in the name.
Save page.
Modify page to include the macro of "

".
Type in sample text within the excerpt frame.
Save page
2) Create a new page or modify an existing page to include excerpt.

Type in your previously saved page under step 1 as a parameter value for the excerpt include.
Save page
3) Notice in confusion the lack of your excerpted sample text.
Instead, notice that the excerpt references that your excerpted page does not exist.
"The page [Page:Title] could not be found."
4) Navigate back to your original page containing the excerpt.
Rename that page to not include the special character.
5) Navigate back to the referring page from step 2.
Modify the excerpt include reference for your newly renamed page without the excerpt.
Save page
Notice in relief that your excerpt reference has now been found.
6) Conclude that by isolating your variables and process of elimination that the special character handling for excerpt inclusion is suspect.
7) Note the workaround of not using special characters and take a little break.