In this thread you can post your bug reports for the lastest version of the Lite Campaign V3 (Patch 6 and the upcoming Patch 7 release). This includes perceived imbalances and all kinds of non-fixture or body related issues. For those, please visit these threads:
Car body issues: UE4 Open Beta Body + Variant Issues list
Fixture issues & suggestions: Fixtures Bug Reports & Suggestions
For support issues, visit the support section instead and make a new thread there after you have checked out the pinned threads found here:
Make sure to always as accurately as possible describe how to get the bug and provide a screenshot of the issue if that serves clarifying the issue.
Cheers!