Welcome luite. A custom viewer, that's a nice project!
There should be very little difference between the emulator and the real device except for hardware related stuff. I can't think of anything that is relevant to UDS plugins.
I've tried your plugin but it does not load on my emulator. Installation seems fine, but UDS fails saying "Error create library for /usr/lib/uds/libuds-plugin-djvu.so". Although "create_plugin_library" returns without error, calls to the plugin library fail. Are you sure the zip contains the same binary which worked on your emulator?