LCD just blinks

I have that exact LCD + Backpack. It uses Address 0x27 in my case. All the address pads are UNsoldered.
It does come with built in pull-up resistors, so it should be plug-and-play. I used a LiquidCrystal_I2C library which worked the first time I tried it.
As long as you wire everything up properly, I see no reason for it not to work with that specific module.
This library looks nice, it's not the specific one I used, but it seems to be derived from it.
http://playground.arduino.cc/uploads/Code/LiquidCrystal_I2C_85V1.zip