"Space With Excerpt" auto-complete only uses space names, not space keys
The "Space With Excerpt" auto-complete in the ME-Include macro editor only uses space names, not space keys.
This makes it difficult to use when editing a newer version of the macro for the use-case of an include across spaces and the include was written pre 5.2.9 (when the "Space With Excerpt" parameter was added).
Users are editing such macros because of bugs that are mauling the "Page With Excerpt" parameter when the macro editor is opened (CMEP-251, for example). The newer versions of the macro editor do no account for older macro versions that may not have a "Space With Excerpt" parameter and they ruin the "Page With Excerpt" parameter by prepending the current space to it, even when it already has a space key prepended to it.
users work around this by editing the macro to add the "Space With Excerpt" parameter to add the space key there. They only see the space key in the existing "Page With Excerpt" and if they don't know the name of the space for that key then they are stuck and need to go find out that space's key so they can type it into the "Space With Excerpt" input.