I have a korg D1 and I am using the demo of pianoteq I noticed my  digital piano  can only get about 95- 100 velocity when playing hard ,  it can go to 127 but I have to hit the keys really hard and could not play the piano like that.  I am new to vst and would like to know if it matters that my piano cant get the full range 127,

Controller keyboards differ, as do players' tastes and playing styles. For that reason, Pianoteq has an adjustable velocity curve tool. You can use that to map an input velocity of 100 to be interpreted as 100% (instead of 78%), for example. It can also be configured for medium velocities to be interpreted as higher or lower values, depending on the linearity of the keyboard (and your preferences). HTH.