The issue might be related to the fact that the LCDd can't claim the usb interface of picoLCD because it's hold by kernel. Can you try to blacklist the picoLCD device (use lsusb to get vendorid/productid) by adding in your bootloader the following at kernel command line:
usbhid.quirks=0x04d8:0xc002:0x4
If you usb hid driver is compiled as module you will need to add similar line
to modprobe.conf
options usbhid quirks=0x04d8:0xc002:0x4
Where 0x04d8:0xc002 is the vendor:product id of picoLCD and 0x4 is the command to ignore this device and not bind to hid driver.
Documentation from kernel source:
Example of modload quirks usage: passing "quirks=0xcd5:0x1:0x4" at
boot tells the USB HID driver to ignore (0x4) vendor ID 0x0cd5, product
ID 0x0001. HID quirk values are defined in include/linux/hid-quirks.h
