I do not own a Tormak mill, but the specifications of the test block seem ok to me! If you take in to consideration the end mill is supported on one end only, that the amount of flex and deflection will increase as the feedrate incrases!
Also, how accurately was the head trammed square prior to running the test?
The other element to take into consideration is the quality of the endmill! Some endmills have a slight taper even when new!
The only true test to the machines squareness is to sweep the table with a .0001" dial indicator mounted in the spindle!
Eric