Unfortunately sysupgrade is not yet implemented, you should go back to wikigear stock firmware then flash the new image

• download the latest trunk revision (you must use trunk because there are not a stable brach with gemini support):

svn co svn://svn.openwrt.org/openwrt/trunk/

• add all available packages (download then “install”):

./scripts/feeds update -a
./scripts/feeds install -a

• manually patch linux sources (https://dev.openwrt.org/attachment/ticket/6998/006-wbd111-enable-usb.patch)

Open arch/arm/mach-gemini/board-wbd111.c and add the green line in the right position
Open drivers/usb/host/ehci-hcd.c and replace the zero with one in the correct line 

• prepare your image (remember to select everythings you need):

make menuconfig

• prepare your kernel (this step is uncommon, but it's indispensable for wbd-111):

make kernel_menuconfig

In this step you should include the right usb drivers but at this moment I don't remember exactly the name in the configurator, however the device is echi-fotg2xx. To check if you have selected the correct driver after flashing image

dmesg | grep -i ehci-fotg2xx

should return

ehci-fotg2xx ehci-fotg2xx.0: Found Faraday OTG 2XX controller (base = 0x68000000)
ehci-fotg2xx ehci-fotg2xx.0: FOTG2XX EHCI Host Controller
ehci-fotg2xx ehci-fotg2xx.0: new USB bus registered, assigned bus number 1
ehci-fotg2xx ehci-fotg2xx.0: irq 10, io mem 0x68000000
ehci-fotg2xx ehci-fotg2xx.0: USB 0.0 started, EHCI 1.00, overcurrent ignored
ehci-fotg2xx ehci-fotg2xx.0: role detected: Host, 
ehci-fotg2xx ehci-fotg2xx.0: A-Device
ehci-fotg2xx ehci-fotg2xx.0: role detected: Host, 
ehci-fotg2xx ehci-fotg2xx.0: A-Device
usb 1-1: new high speed USB device using ehci-fotg2xx and address 2

• make the image (where 2 is the number of your processor's core):

make -j 2

• Download and apply the patch to openwrt sources attached in this ticket.