I've been working on warehousing software for the last three years, integrating various pieces of automated machinery and humans with handhelds on two continents...

Best advice I can give you is non-technical - you (usually, and probably doubly so during a recession) have some bright people working on the floor, find and empower one or two of them to guide the software process. Life became much easier when we had a "product super user" who used to be one of the floor managers for a specific set of processes, who was able to tell us what processes wouldn't work, help us think of stuff we hadn't, who knew where stock shrinkage was likely to occur, and so on...