Some googleing suggests, that installing the kernel module r8188eu might work; if that doesn't work, the kernel module rtl8192cu is your other chance. I didn't find any other hints than these two.

Both modules are on the feed (if you use the VTi image at least): try blue->Software Manager->Kernel modules. Note that you need a temporary internet connection, preferably with a ethernet cable.

On your remote press the blue button, then choose Software Manager, and after it has fetched the software packets list, choose Kernel modules, where you need to scroll down to select the two modules I mentioned. If you use the VTi image. I can't help you if you use the original or any other image

Have you tried to reboot your box? Is your SSID hidden (it better should not)? Sometimes passwords containing special chars cause problems (at home I can't even use the space char...). Other than that, I have no idea.

youi schrieb:

DWA-123 ver: D1

Correct kernel module shouold be "rtl8192cu" according this site: click (german but with links to english sites)
Usually you can't download a kernel module (aka "driver") without issues because most of them rely on specific kernel versions.

From my point of view this seems to be a problematic stick within linux OS. I suggest you to buy different one.