Issues with speed/Cannot create new sidebars

We've been using your plugin Custom Sidebars (v. 2.1.1.4) since March 2016. We have over 60 custom sidebars each with their own text options and maps. In the past it's taken up to five minutes to add a text section; your plugin causes Firefox and Chrome to freeze. This week (10/24/16) we upgraded to your latest version, and now I can't add new sidebars - your plugin once again freezes. We have a project due next Friday and need to fix this ASAP.