We are going through a same problem. We have spent about 1 year in developing our game. All the code is written from scratch by us in unity. For design, we purchased some of the assets pack from unity asset store & we do have the licence to use them.
Still, we received this same message (Guideline 4.3 - Design) from the App Store review team.
We are not sure about what to do now? Even the review team were not specific about issue. Also, changing anything will welcome unnecessary bugs.
Topic:
App Store Distribution & Marketing
SubTopic:
App Review
Tags: