You need to make basic instalation on internal storage / for 4.4.2 and up / - without maps, poi ect... and follow the instructions from [Only registered and activated users can see links. ] from [Only registered and activated users can see links. ] to place maps, poi, ect to external SD card .
Another way is to root device and make permissions RW for apps like iGo ... easy way is SDCardFix - then all can be on external storage.
The name of SDCard is important, so use Something like TotalCommander or ESFileExplorer to see how is named own in your device.
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