In that case I recommend an outboard program for your velocity curve.
I use one called Velocity Curve. This one behaves much like fthe one built into Pianoteq.
Unlike Kontakt's velocity curve -- with its ridiculous field-of-grass interface -- Velocity Curve lets you drop points onto the curve and then slide the dots up and down.
The author seems to have abandoned the web site … but I saved the program on Google drive for anyone to download: