You are misunderstanding the problem here:
Your device has not enough internal memory to store such a big map.
My suggestion would be to make a full backup using Windows Explorer and after that to download one of our maps with the coverage you need.
I don't know what coverage you need but there are several EU maps available with meta codes in the 900 collection.
If worse comes to worse you might miss out for the trip on a few map feautres, but wou should be able to find a map that covers your trip.
Only other option be using something with more memory or an entirly different system.
In case you are willing to get into the guts of your device you can check my tutorial on adding a SD to most TT models - if you have a similar layout you might be able to add an SD.