[PD] trouble with data structures

I'm writing my first piece that will take advantage of data structures in PD, and I've stumbled upon an error that I do not understand.

I have two structures drawn in the same subpatch. One is a sequence of notes, the other is a playhead. The sequencer was working fine until I added the playhead. Now whenever I try to get data from the sequencer (getsize, get) I receive the following error:

error: getsize pd-instr1: got wrong template (pd-playhead)

My patch is attached below. Is it not possible (or not advisable) for two structures to draw to the same subpatch?

(The csoundapi~ object is used to generate the sound for this patch, but is unnecessary for duplicating the issue...)

Thanks in advance for any advice... Julian Peterson