Once after installing/upgrading BizTalk360, you may face a problem like the icons are not displaying. So that you can't able to navigate to the BizTalk360 Settings page as well.
This problem appears because of the permission/feature lagging.
Please check the following this which will help you to resolve the problem:
1. The Service Account should have Admin privileges to access the installation folder
C:\Program Files (x86)\Kovai Ltd
2. The static content should the activated under IIS
IIS-> Wold Wide Web Services-> Common HTTP Features-> Static Content