When I'm trying to rig socks to conform to a model, this is usually what I get:

When zeroed, the socks look fine conformed, It's when the legs bend the issue starts.  Any tips? Anything I'm doing wrong?

Is there a way to transfer the JCM's and magnets to to the stocking figure or at least modify them?

The "Copy Joint Zones From..." will transfer the JCMs from V4 to the stockings.  If the figure is the traditional V4 with magnets, then you must use the provided magnet props to make the stockings fit better.  I use the weight-mapped version of  V4 or Sasha which have the magnets stripped from the figure.

I went ahead and copied the JCMs and magnetized the conformed socks (Am I doing this right). It's better, but still has issues. 

What are your Properties tab values?

This is from the sock figure:

Is there a reason why you don't want to make V4 legs invisible?  The whole concept that we have to leave every single polygon visible and hope to make two objects mirror each other with the perfect amount of offset to hide one set of polygons that should be hidden is a massive waste of time.  You have to ask yourself what is the final result suppose to be?  If you turn off the visibility of the legs then the poke thru would be gone. In this case the best way to do it is to make a mask to turn off the texture under the sock.

Because if you make socks in various lengths, there's only so much hiding the legs can do.

This is how it looks with the right shin hidden.

Is there a reason why you don't want to make V4 legs invisible?

I'm guessing he's trying to develop a product, possibly a store product where "making Vicky4's legs invisible" is not a viable option, which I may add, it is not the best option here. What if he wants the socks to have a transparency option?

And if you use a second skin effect much like the painted on Bra that V4 wears then you change the length of the mask and that changes the height of the sock.  And it follows the bending just as the model since it is the model.  Different masks can be made to make parts see thru such as fishnets.  About the only thing you need to make is a toe cap to hide the toes the rest can be a texture map.

Since the effect is to be skin tight makes it much easier to do.  Maybe add a couple of morphs to smooth the ankle etc. and be done.

I'm interested in the 2nd skin effect.  How do I make use of it?

Use the Morphbrush (Tighten/Losen Fit) with the V4 figure selected as a goal to create a fit morph.

Then set this morph up as a JCM.

2nd skin is generally preferrable, but some stockings are too elaborate for this to work.

Also, if you need to drastically morph a figure, a 2nd skin stocking will distort. An actual stocking mesh can be "bespoke UV mapped" to fit the final morph.

Here's an early WIP for a V4 character I'm working on:

The skin texture still works quite well, but' I'm pretty sure all clothing needs to be heavily modified or custom made to look good on her.

I'm trying to use multiple layers on models but when I try to apply a material on a layer, it does so on the base layer instead.  Is there something I'm doing wrong?

The "Copy Joint Zones From..." will transfer the JCMs from V4 to the stockings.

No it won't.

I am trying to upload pictures to show how to do a second skin effect.  See if this works.  Pictures won't attach.

Here is LaFemme with her legs masked. You make the mask as a Black and White picture.

Here is the mask that I made to select only her legs.

And this is the Material room settings.  All the expanded nodes towards the bottom are the ones that I put in.  It is also using one of My Expandeable 2 Color Ramp compound nodes.  Look in the Freebies section under my user name and you can find the download to make use for yourself.  You are allowed to used them any way you need to in both Freebies and paid products.  By changing the value of Pos 2 that changes how far up the material swap is made.

And here are two pictures with the position changed for a low sock and a high sock.