It sounds like you'd like to set the "Condition" annotation to everything after the date at the beginning of the filename and before the "s#_inj#" at the end.
Some of your replicate names have a "_s#" and some do not, so I would probably accomplish this with two different rules.
One rule would match:
[0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_+(.+)_s[0-9]_inj[0-9]
and replace it with:
$1
and the other rule would match:
[0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_+(.+)_inj[0-9]
and also replace it with:
$1
Here's what that first regular expression does:
[0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_+(.+)_s[0-9]_inj[0-9]
The "[0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_" matches 4 digits followed by an underscore, 2 digits, another underscore, 2 digits, and another underscore.
The "(.+)" matches one or more occurrences of any character.
The "s_[0-9]_inj[0-9]" matches the stuff at the end of the filename.
These rules make the "Condition" annotation get the correct values in the Rule Set Editor.
The condition values do not actually get updated in the document because "Condition" is a Value List, and the list of values do not quite match what the rule is producing.
You should edit the Annotation definition and probably change it to "Text".
By the way, here's a page with more information about Result File Rules:
https://skyline.ms/wiki/home/software/Skyline/page.view?name=ResultFileRules
-- Nick