what happened to edit > backdrop
So, where is Edit > Backdrop? It does not appear in the Edit pull-down menu as an option.
From the DAZ Knowledge base:
Bringing Photoshop Files into Studio
It's important to be aware that Studio is primarily a 3D application and that Photoshop is primarily a 2D application. You can bring 2D pictures from Photoshop into DAZ Studio. To do this, save the picture in Photoshop in a format that can be used in Studio, such as .jpg, .png, or .psd. The Photoshop Document format can be used in MLIE (Multi-Layered Image Editor). Otherwise, the .jpg and .png formats are standard. There are two ways to use 2D files in Studio. You can use a 2D file, such as a .jpg file, as a backdrop. You can apply a 2D file to the surface of a model.
To create a backdrop in DAZ Studio 4, go to EDIT --> Backdrop. In the new window, browse to and select the 2D file that you wish to use.
Comments
Note that the DAZ knowledge base excerpt referes to DAZ 4...
There's a new pane called 'Environment'. That gives you all the backdrop options.
http://www.daz3d.com/forums/discussion/comment/718267/#Comment_718267
Do you have a link to the Knowledge Base article?