If no styles folder is present in the directory of the NeoLemmix player and one clicks on "Force Redownload All Styles", one gets an error message "Could not find the file path '.../styles/versions.ini'".
Instead the player should simply create a new styles folder and create the versions.ini file inside this new folder.
PS: Thanks to Flopsy for finding this bug.
Will sort this out somehow. It's not too critical because this option only redownloads styles the user already has; if there's no "styles" folder, they don't have any styles yet anyway. (On this note, perhaps a "download all available styles" option should be added, nonetheless; or even something like in the editor and Flexi to allow manually downloading styles before they're needed.)
Fixed this for next update. I'm also working on adding a "Download All Available Styles" button.