Sustain Pedal Not Working in DAW

Be sure to have selected Minimalistic under Options and MIDI.  You possibly want to set it as a default Global MIDI Mapping.  That way it becomes an automatic option (that is) selected with each new PIANOTEQ instance inside your DAW.

Anytime Global MIDI Mapping shows the word unsaved in parentheses, the setting has been somehow altered.

Have you selected Any as your Notes Channel?  If you already have, you may need now to refer to your DAW documentation or contact its support.

Occasionally, quirks like bugs come into play especially inside a DAW.

Whenever encountered you may have to look to some sort of a temporary workaround maybe coming from a third (3rd) party software.  One is accessible via your user account.  It is where you as a PIANOTEQ registered user can get Gig Performer at a discounted price.  And, it is also available as a demo.  That allows patch changes.

But to tell whether or not you need it now, you may firstly want to review a thread showing someone else had encountered a problem similar to yours: Pianoteq in Reaper with FCB1010.

Now certainly, if when you right-click on the sustain pedal you see in fact Sustain Pedal selected and are testing one of the default presets —without an italicized preset name showing— you have a high probability of the problem caused outside PIANOTEQ, otherwise DAW related.  Which is likely your case unless you get of course Controller 64 MIDI Events appearing inside the MIDI messages window (that is) under Options and MIDI.  (Beforehand you may need to verify if the connected keyboard even is sending at all Controller 64 MIDI Events verifiable via the PIANOTEQ window inside the stand alone copy.)

An update! The maker of my DAW (MultiTrack Studio) has done some digging and he found that contrary to his belief, VST3 plugins were not properly receiving data from controller 64. He's going to push a fix sometime in the coming week. Thus endeth this saga.