I think I may have blogged about this before, but I can't really remember - and that means it's not a bad idea to revisit the "Projekt Tafelmalerei" of the Germanisches Nationalmuseum in Nuremberg.
The GNM has a very large collection of late medieval paintings on wood, and there's a project to research these paintings and make the information about them accessible on the Internet. The whole thing can be found at tafelmalerei.gnm.de and features 148 paintings, starting in 1260 and ending in 1520. So if you're interested in late medieval artwork, you might want to check it out.
The platform is German only; you find the paintings under "Objekte", and then there's preview images for all the items.
Especially interesting: There's a painting by the Meister von Uttenheim showing the Birth of Mary, and there's a lady dressed in a green gown that has a similar cut to one of the Lengberg dress fragments. Plus she's wearing a headdress with a geometrically ornamented inset - maybe something similar to a cap like that also found in Lengberg?