- "INTEGRATE -> UPDATES" : this is the folder used by WinReducer to integrate all updates you download using the "WinReducer Updates Catalog". Just take care there is for WinReducer 8.1 a special folder structure because of "Update 1" and "Update 3"; you could refer to the sticky WinReducer Updates Catalog forum thread with the mini tutorial in the 1st post : an "Update_1" folder, an "Update_3" folder and an "Updates" folder to store all other updates.
So if you downloaded your own windows updates using another software and you want to integrate them using WinReducer : you have to put all of them in the according folder. But using the "WinReducer Updates Catalog", WinReducer will automatically put them in the good folder.
- "INTEGRATE -> SOFTWARE" : this is the folder you could use to store your software executable to use with the WinReducer OOBE tool (= install software after windows installation). It's also used by the "WinReducer Updates Catalog" to store some software you choose to download (like Visual C++, Silverlight, Malicious Software Removal Tool, ...)
- "INTEGRATE -> DRIVERS" : this is the folder used by WinReducer to automatically integrate your drivers before installation if you activate the option "System - Integrate Drivers".
This solution is not perfect, but fully functional, because you need to extract your drivers manually and put them in their own folder. WinReducer will search for all valid drivers to integrate in your ISO. This work is in progress and will be updated in the future.
Have a good day !