lost everything

I have been using limewire for a year without a prob so i am prety used to its workings now .Acouple of weeks ago it started up not as normal but with the setup banner and i had lost everything including my user setings and partial downloads .i redid everything and started again .when it opened this morning all my old setings , skin and downloads were showing and all the new stuff had gone.Im afraid to use it now incase i lose everything after days of downloading.Anyone have a clue whats going on here , everything else on my computer as always is trouble free and unchanged.Nothing on it has changed or been added to so theres nohing to explaine why.Dave