You need to also install the firmware file,

Some USB Dongles requires an external bin file for the firmware, some already have it in the driver executable file. In the case of your dongle, RT5370 from the Ralink family RTxx7x, you need also the firmware to be installed.

So you need as explained on the post I gave you the link from Admin, you can see you need to install the driver + firmware and then the wireless plugin.

Code:
opkg update
opkg install kernel-module-rt2800usb-3.2-dm800se
opkg install firmware-rt2870
opkg install enigma2-plugin-systemplugins-wirelesslan

Try and let us know the result,

TS
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