Regarding the rule engine:
Depending on the branch you want to build the rule engine needs a build.gradle file. You can check its github repository and copy it.
The problem with the content provider seems to be a missing file. Can you check that the app build.gradle file defines resValue "string", "content_provider", "com.dhis2.xxx.provider" for each buildVariant? If so, add this and change xxx with the proper buildVariant name.