Need help with serial byte array and Motor spin

Dear Arduino forum members,
I am struggeling a couple of hours to build a Project from an old Code example for controlling 2 Motors via Hardware Serial Port.
Perhaps someone else can help me to find out whats wrong with attached Code.
The original Code was for an ADK Board but i wanted to make the Code useable for Nano.
The complete Code is attached as .ino file.
I have tried to upload the Sketch to an Arduino Nano Board but the IDE compiles with following error message:

No Function for call to Serial::read(uint8_t[2] unsigned int)

//Code Snippet
uint8_t rxBuffer[2]; //Byte Array

void loop(){

//Check serial
if (Serial.available() > 0)
{
int len = Serial.read(rxBuffer, sizeof(rxBuffer), 2); // this line throws the error
if(len == 2)
{
// Do something

motoren.ino (1.98 KB)

That means that Serial.read does not take any parameters and you have given it two.

Did the original ADK code contain the exact same code snippet? Or is the line with Serial.read something that you made up? It surely is different from the usual Serial.read (but I have no experience with the ADK).

PS
When posting code on the forum, please use code tags.