Hi Copangtnc,
Greetings!!!
Yes, you can configure it by modifying plugin source attached with the sample. You can change your Notification UI and message format. We have added app42pushserviceV2.jar file in case if you don't want to show the message on Notification Bar if the application is opened.
There may be some issue in AndroidManifest.XML configuration due to which you are not able to receive Push Notifications. Please share your app AndroidManifest.xml file, so that I can help you in a better manner.
You can also share Push Logs available under Push Logs section of Unified Notification section on AppHQ Management Console. If you have not enabled it yet, then please click on AppManger>Settings and click on Enable button under Push Logs option.
P.S Please share the requested details, it will help us to find the root cause of this issue.
Thanks
Vishnu Garg