Although IFFSnooper is designed primarily as a tool to view the contents of an IFF file, it also permits resource export and reassembly. It is therefore possible to create a new IFF file for the game, if you know what you are doing. It is also possible to create a file which won't work at all, if you leave out some vital piece. Consider IFFSnooper as a research tool, not a full-fledged object editor.
To save a folder full of resources select
Export -- Disassemble
To convert a folder full of resources into a binary file select
Import -- Resources in IFFSnooper 1.0.7 or later
Import -- Assemble in IFFSnooper 1.0.6 or earlier