I am not sure I understand what you want? Do you have a Select dropdown box set to multi-select mode, and you want to select all options? This is, in effect, the same as not selecting any. If you want to do this, there is not an option in the plugin, but it may be possible using third party custom javascript coding. If you wish to try this yourself, you can most likely get tips from the stackexchange snippets (Q&A) site for self-coders.