Posing Genesis 2 clothes on regular Genesis
So, I have the plugin that allows you to fit Genesis 2 outfits on the regular Genesis model, and I'm grateful for that. However, I've found that certain G2 outfits don't seem to pose very well on G1. This dress, for example:
http://www.daz3d.com/boulevard-dress-for-genesis-2-female-s
I can put the Genesis figure in the sitting positions, but when I try to put the dress in those positions, the skirt flies up in her face. Is there any kind of plugin, or some way I can fix that problem?
I don't have a lot of skins for G2 yet, and I've seen some nice upgrades for G1 that don't seem to be available for G2. (at least not that I'm aware of) Like this one:

Comments
If you get Generation X, or use the transfer utility, you can transfer any Genesis morph to G2F. Likewise if you have the product that allows you to put V4 skins onto G2F (http://www.daz3d.com/victoria-4-for-genesis-2-female) then you can put the vast majority of Genesis skins onto G2F.
Regarding your original problem, any clothing, and in particular long skirts, may have issues when transferred via autofit or another automatic transfer method. They will always work best on the figure they were created for.
I see. Thank you.
You could try using the Transfer Utility on the clothing rather than AutoFit. Sickle Rigging and Morphing System would likely help too.
Sickle's stuff does help a lot with skirts and dresses. I originally bought it because I planned on making a bunch of Gen/Gen2 clothing, that I haven't gotten around to making yet, but what I have used it for comes out a lot nicer than without it.