I've been playing with one of these uOLED-128-G1 displays recently. I found Paul Karliks library, but it only supports a subset of the functions that the board is capable of. Most importantly it didn't have a method to cleanly shut down the OLED display to prevent damage. So I went about making a new one.
It is in no way optimal, but it works, and it's (nearly) complete. Important to note that it requires NewSoftSerial, so you can attach the display on any pins. Currently the serial object is passed by reference when you create the display object, see the example file. It also blocks execution until each command is acknowledged by the 4D chip (the timeout is changeable in the header file, defaults to 1 second)
It implements all of the SGC commands from the 4D reference sheet except for Polygon, Image, and Tune (which I didn't really need and have been too lazy to put in).
Wherever possible I matched 4d function names. ACKs and NAKs are returned as booleans, and the occasional flag value was changed from int to bool parameters. I also changed commands like UserBitmap which accept 8 individual bytes for data to instead take a byte array.
If you're not using the power or reset pins you can just set them to -1 and they'll be ignored by the library.