Magix Vita Instruments can be automated via the right click menu. Make a right click on a control you want to automate and select a MIDI control number (not host control). You can select a continuous controller number between 0 and 127. You can draw a curve for each of the continuous controllers in the MIDI editor, just select a number you have previously assigned to a control. Don't get confused by the premade names of the controllers in the MIDI editor. Only the number is relevant.

If you have a MIDI controller with automation capabilities you can also right click on a control and select MIDI learn and move a fader or knob to assign it to the control.

Other plugins can only be automated if they have a similar MIDI learn or MIDI controller selection feature since Music Maker lacks deeper track automation.

You would then need special VSTs to overcome this limitation like Pluginguru Unify.