Here is a link to a video that shows how to install the microSD card on a Nuvi device. This is NOT the Nuvi 55LM, but the concepts are all the same, including how you TEST and VERIFY that the maps are enabled and working.
Click link below for video.
One other note: Another advantage to using the preprogrammed map card is that it will not disturb the Lifetime Maps (coverage area) that are already in your device. That is, when you are done with your Poland trip, you simply unplug the card (if you want to), wait for the device to lock on the satellites to find your location here, and you are "back to normal" with the device.
Please let me know what you find or if you have any more questions.
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