In Reaper's "parameter modulation/Midi link" mode, the widgets of two Cabbage patches are linked and updated only manually and not if you transmit the values from within the patch

Cabbage Stew
5

So the reason this is happening is because Cabbage plugins don’t broadcast automation changes by default. For this to work simply add the following line of code to the top of instrument one:

chnset 1, "CSOUND_GESTURES"

After this, the plugin should behave as you want. For more details about this reserved channel see here

I have to admit, I had almost forgotten about this feature :rofl: