I found the code to update the screen. It is in the ZLApplication.cpp in the /zlibrary/core/src/application folder. I think you will only need to add the xepdmgrclient.h to this base class and call the correct screen update methods. I believe in this case it may be the EpdRefreshFull() method.
I don't have a working dev environment so if you can test this along with the scrollingaction.cpp updates it would be great.
Code:
void ZLApplication::refreshWindow() {
if (!myViewWidget.isNull()) {
myViewWidget->repaint();
}
if (!myWindow.isNull()) {
myWindow->refresh();
//code to update screen should go here
}
}