Actually, IMHO, there are 4 very essential commands that u should know. If u know them, you'll be pretty OK.    
1. TMS Fwd Long = Make SPI 
2. TMS Aft Long = SPI to Steerpoint 
3. China Hat Fwd Long = Slave all to SPI 
4. China Hat Aft Long = Slave TGP to Steerpoint