If you ever decide to use Wildcard module on the Sitecore 8+ solution, you will find that wildcard rules editor doesn’t work as expected.
This happens because the Rules tree structure has been changed a bit since Sitecore 7.1. (read more)
Below you will find a set of steps to perform in order to re-enable the wildcard module for Sitecore 8.
1. Add new Wildcards Element under the /sitecore/system/Settings/Rules/Definitions/Elements folder
2. Move every Action/Condition from /sitecore/system/Settings/Rules/Wildcards subfolders to the Wildcards element created before. You can delete the old item if you want.
The result should look like this:
3. Add a new Wildcards tag under /sitecore/system/Settings/Rules/Definitions/Tags
4. Navigate to the Wildcards tag configuration item /sitecore/system/Settings/Rules/Definitions/Elements/Wildcards/Tags/Default and select the Wildcards tag from the list:
5. Create a new Wildcards Rule Context Item under /sitecore/system/Settings/Rules
6. Select a Wildcards tag in the Tags list for the above created Rule context item:
7. Finally, go to the /sitecore/templates/Wildcards/Route template and set /sitecore/system/Settings/Rules/Wildcards as Rules field datasource.
As a result, you can edit the wildcard rules as expected: