How to read/use ISA Performance tables?

Hi all,Untill now I never concerend to interpretate the ISA performance tables of GA aircraft correctly.Now I'm at a point that I would like to use them in a correct manner.Can someone explain how to use the ISA table based on an airports altitude, QNH, temperature and maybe more variables?For example for the Piper Cheyenne IIXL I have the following data:(besides a whole range of other pressure altitudes) Max Cruise 1900RPM ISAPressure Altitude: 10,000ftIOAT: 0OAT: -5Torque: 1714 lbsTAS: 267What calculation(s) should I make to use the table correctly?I hope I have made myself a bit clear ;-)