i found another problem : if you do a actor.MarkGeomChanged() before even doing a FigureCollect() you'll have a total mess undo. For me the figure merged with the figure it was conformed . removed it and undo worked this happens in Poser 11.1.1.35510.

Logs :

figure Collect:(figure and actor)
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'BODY:2'//obj:'|Actor object at 0x00000000135AF708|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'CenterOfMass:2'//obj:'|Actor object at 0x00000000135AF1F8|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'GoalCenterOfMass:2'//obj:'|Actor object at 0x00000000135AF600|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'hip:2'//obj:'|Actor object at 0x000000001353BE10|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'abdomen:2'//obj:'|Actor object at 0x000000001353B960|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rThigh:2'//obj:'|Actor object at 0x000000001353B660|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rShin:2'//obj:'|Actor object at 0x000000001353BDB0|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rFoot:2'//obj:'|Actor object at 0x000000001353B7E0|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lThigh:2'//obj:'|Actor object at 0x000000001353BB58|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lShin:2'//obj:'|Actor object at 0x000000001353BA50|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lFoot:2'//obj:'|Actor object at 0x000000001353BD08|'
figure Undo: (figure and actor)
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'BODY:2'//obj:'|Actor object at 0x000000001353D798|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'CenterOfMass:2'//obj:'|Actor object at 0x000000001353BAE0|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'GoalCenterOfMass:2'//obj:'|Actor object at 0x000000001353BEA0|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'hip:2'//obj:'|Actor object at 0x000000001353B948|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'abdomen:2'//obj:'|Actor object at 0x000000001353BD08|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rThigh:2'//obj:'|Actor object at 0x000000001353B9A8|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rShin:2'//obj:'|Actor object at 0x000000001353BE10|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'rFoot:2'//obj:'|Actor object at 0x000000001353B960|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lThigh:2'//obj:'|Actor object at 0x000000001353B660|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lShin:2'//obj:'|Actor object at 0x000000001353BDB0|'
figure 'V4Hot_Shoes':'Figure 2'//obj:'|Figure object at 0x000000001353D3A8|', actor 'lFoot:2'//obj:'|Actor object at 0x000000001353B2A0|'
dictionary data before calling and figure checking name/internalname : ac = figure.ActorByInternalName(ac_dict["InternalName"])
figure 'V4Hot_Shoes':'Figure 2' // actor 'BODY:2'
figure 'V4Hot_Shoes':'Figure 2' // actor 'hip:2'
figure 'V4Hot_Shoes':'Figure 2' // actor 'abdomen:2'
  File "F:LocalRuntimeLibraries!BarzingsplitCR2.py", line 609, in undoFigure
    ac = figure.Actor(ac_dict["InternalName"])
poser.error: Figure has no actor by that name
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