Vila, Those levels of warnings are there to let the developer know about potential issues. This does not mean that your application will not work. Native libraries are supported in latest BlackBerry Android Runtime so you should not have issues, but don't forget to bundle them with your application. Also, be sure to be using the latest dev tool to convert your APK to BAR FILE.
https://developer.blackberry.com/android/tools/
Find here also the API support to ensuer you will not have issues with your app features https://developer.blackberry.com/android/apisupport/