Plz advice/comment on my Gridseed gc3355 status

Hi all,

I'm new with Gridseed gc3355, and wanna ask: does someone meet the same problems as I did?

there are tons of hardware errors with https://github.com/gridseed/cgminer-3.1.1-GC3355-SV's cgminer - see http://pastebin.com/912CEYDd,
both https://github.com/dtbartle/cgminer-gc3355's cgminer-gc3355 and https://github.com/girnyau/cgminer-gc3355's one give me neither one coin nor any transaction during long mining time (and, what is amt=0 err=-7 ern=110 error?)- see http://pastebin.com/HB4RGbCi when debug option was activated,
no bfgminer for me, because both https://github.com/nwoolls/bfgminer's bfgminer and https://github.com/luke-jr/bfgminer's one configured with configure --enable-scrypt --enable-gridseed and running as bfgminer -S gridseed:all --set-device gridseed:clock=850 --failover-only --scrypt -c somewhere/mypool.conf complain with NO DEVICES FOUND, and cannot find Gridseed neither in auto nor manual specifying the /dev/ttyACM0 device,
and, only https://github.com/pooler/cpuminer works and makes ~250KH/s for me, but I'm not sure whether CPU mining is effective/good for Gridseed?

My single Gridseed looks good from Linux sys logs:

Code:

[ 1061.362011] usb 5-1: new full-speed USB device number 2 using ohci-pci
[ 1061.501876] usb 5-1: device descriptor read/64, error -62
[ 1061.745649] usb 5-1: device descriptor read/64, error -62
[ 1061.985424] usb 5-1: new full-speed USB device number 3 using ohci-pci
[ 1062.160237] usb 5-1: New USB device found, idVendor=0483, idProduct=5740
[ 1062.160250] usb 5-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1062.160257] usb 5-1: Product: STM32 Virtual COM Port  
[ 1062.160263] usb 5-1: Manufacturer: STMicroelectronics
[ 1062.160267] usb 5-1: SerialNumber: XXXXXXXXXXXXX
[ 1062.245954] cdc_acm 5-1:1.0: This device cannot do calls on its own. It is not a modem.
[ 1062.245982] cdc_acm 5-1:1.0: ttyACM0: USB ACM device
[ 1062.248258] usbcore: registered new interface driver cdc_acm
[ 1062.248260] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters

Any practical advice or comment for me? Thanks.