When routing an arpeggiator to an instrument can't open the arpeggiator for editing

I have upgrade my Cubase Elements form 10th version to the new 12. In Cubase elements there are no midi FX. I use the Cream arpeggiator in an instrument track. the input of the track is my midi controller. the out put is directly to a vst instrument (Choosing from a list of all the vst instruments. In version 10 the output was to an instruments channel).
So there is only one channel with the arpeggiator and it’s routing to an instrument which doesn’t seat in a channel of its own.
When I want to edit the arpeggiator, I click on the keyboard sign in the channel and the instrument is open up. Not the arpeggiator.
What have I done wrong?
Thanks for the help