One last update... and a shameless beg for help...

I have been studying FagTop and FagBottom and schotMain and pulleyDeck until my eyes are bubbling... but I just can't figure out what I'm missing. I've got the whole thing working... with the exception of the mainsheet not stretching:

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The mainsheet is welded to the Bottom pulley and to the boom pulley... so when the boom swings out, the two pulleys point at each other whilst the mainsheet also moves appropriately - it's all good, except for the mainsheet top - the bit that is welded to the top pulley. It appears to come away when the boom swings out. I opened the .cr2 in Notepad++ to double-check that all the bits are welded... and they are:
    weld    SternHatch:1  
             Hull:1
    weld    Tiller:1  
             Hull:1
    weld    Track:1  
             Hull:1
    weld    TrackSlider:1  
             Track:1
    weld    PulleyTrk:1  
             TrackSlider:1
    weld    MainSheetAft:1  
             PulleyTrk:1
    weld    MainSheetAft:1  
             PulleyTop:1
    allowsBending 1 
    figureType 1318 
    origFigureType 1318 
    canonType 8 
    conforming 0

I've got bend set to 1 for the MainsheetAft - I thought that governed stretching. I noticed that you had forceLimits set to 4, svdl - I guess you didn't want Poser to over-ride your settings, right? I'll probably do that as well.

I feel I'm so close... just that one glitch to overcome... if you want, I could post the .cr2... but only if that's okay with you.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

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[it is clear that humans have contempt for that which they do not understand] 

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