There is a closed topic that mentions this about a year ago but the problem still seems to exist.
I deactivated and reactivated the plugin and all the settings were lost. It isn't just customizations that were lost, every field is blank, even the radio buttons. I have tried adding the settings back in but there are many I can't remember what the defaults were. A reset to defaults button might be handy.
Also, no matter what I set the height to the slider height is 3px!