You could try using the Limits to keep the morph at 1. Something like this:

targetGeom rightarmup
  {
  name rightarmup
  initValue 0
  hidden 0
  enabled 1
  forceLimits 1
  min 1
  max 1

Note that Force Limits is 1, and min and max are both 1. The Zero Figure command doesn't zero this morph.

This may not work with a spawned morph; I think those are different somehow.... but it definitely works with a 'regular' morph that has deltas.

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