This sounds like your pedal is not being recognized by Pianoteq.
Try this :
1. Start pianoteq and your keyboard as usual
2. Click on "Option". This will open a dialog box.
3. In the Options dialog box click "MIDI".
From this MIDI information and controls can be selected and midi messages are displayed, which helps check your pedal.
If you press down on your pedal ( you don't need to be pressing a key ), a message should appear in the MIDI window showing something similar to "Controller 64 Value 127", but with different numbers perhaps. If no message appears then your pedal is simply not being seen by Pianoteq. Another message should appear when you release the pedal.
You can ( from that window ) map the controller ( your pedal is a controller in MIDI ) to any pedal ( or other control if you wish ), so the first thing is to find out what happens ( if anything ) when you hit the pedal. Maybe someone can help after we know that.
StephenG