Hi Haloedrain - thanks so much for considering my little problem. The only reason I know about all this nautical stuff is I used to sail with friends a lot and became quite the enthusiast, and they got tired of hearing: "Oh, you you please just throw me the thingie..."

Quote - ... is there a way to link a morph to another morph?  I.e., you have a morph for the boom

I've actually imported the hull obj into Poser 7 as a separate entity to the boom/sail obj group. The main reason I did that is because I want to be able to set Smooth Polygons on for the hull but not for the boom and rigging, because it renders weird. However, this allowed me to set how I want the boom to behave (swing back and forth) using the joint editor and even set limits and removed xtrans, ytrans, ztrans and xrotate, zrotate by opening the .pp2 and editing out those features.
I had to parent the boom/sail assembly first to the hull so that when the vessel heeled over (tipped to one side) - as they do when the sails fill and draw - the boom/sail group would tip in the same direction.
So, this is the background against which I'm going to be doing those morph thingies with the mainsheet. The boom swings as the user twiddles the yrotate (renamed "Swing", since that's kinda what it does - it swings out, right?)

Quote - ... one for the lengthening rope, and changing the boom morph also changes the rope morph...

Since the boom just swings on the y-axis - limits set to -30 - I suppose the morphs would have to somehow be associated to some defined point on the boom, perhaps? I guess I need to get a grasp on how to create prop morphs for Poser - the modeling in Blender would be the easy part! (Geez, I do like Blender... it's alway so hard to go from Blender when everything is so intuitive and quick - to Poser, where just moving around the workspace is so awkward... :S...)

Thanks again, Haloedrain... :)

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

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