It is very unlikely that you will need to do this, and it requires you to be familiar with the use of Finder or Explorer.
The steps for removing add-on packs are as follows:
Mac and Windows
- Open the plugin
- Open the FILE menu
- Choose Browse/Manage...
- Click USER
- Find the Add-On pack.
- Right click, and choose Show In Explorer or Show In Finder (Mac).
The filesystem will now open and show you BigKick user presets folder structure.
- Remove the folder for the add-on pack, e.g. Xyz Big Kicks.preset
- Navigate up a couple of folders in Exporer and find the Attacks folder.
- Find the pack's attack folder inside Add-On packs in your Attack folder
- Navigate up to the BigKick folder.
- In the Sounds folder remove the add-on pack's samples and containing folder.