This setup is with respect to  Oracle Applications 11.5.10.2 instance.

First apply patch - 6898666. This patch is available via Metalink. As always, please review the prereqs. If you are patched up to 11.5.10.2, you should be fine.

In order to upload budgets with Excel, you will need to create the profile option, "GL: Default Desktop Viewer". You can find more information pertaining to the steps for setting up this profile option in Metalink note 556280.1.

When trying to upload a budget for the first time, you may encounter the error: "You do not have permission to access this functionality". This error is normal. It can be corrected by setting the profile option: "BNE Allow No Security Rule" to Yes at the Responsibility level. You can find more information pertaining to this error in Metalink note 559924.1.

With the three steps above you will be uploading budgets via WebADI in no time.

Setup for for multiple sets of books

First create a new responsibility for WebADI, similar to the WebADI responsibility seeded. (Copy the menu name and data group seeded in the responsibilities setup form.) 

Associate the new responsibility with the SOB via the "GL: Set of Books Name" profile option at the responsibility level.  

Assign the responsibility to a user.