I connected and tested my gimbal (http://www.ebay.com/itm/251410771764) and right out of the box it worked fine. In fact it worked great. Connected to my Phantom 1 all was good (I did not connect the third wire to control pitch). I wanted to reset the pitch I had established when I first connected it so I thought I would use the SimpleBCGGUI to do so.
I'm not sure what I did but now it's just a jittery mess that won't sit still and tries to continuously rotate. I've tried to "restore defaults" and while that seems to take, it has no real affect.
I'm not much further along than you but try this: go to bangood.com and search for SKU SKU105675
Then scroll down to "For English Manual And Instruction,Please Click Here" and download the ZIP file. (*** Unless your gimbal came with files or a link to get the source files***)
Extract the ZIP file and in the folder "SimpleBGC_GUI_2_2b2" you'll find a file called TH go3.profile
In the Profile section of the SimpleBGU software , click Load to load that file to your gimbal. Be sure to Write it as well.
That should get you back to a starting point. (Which is where I am).