When I started working on adding the cooldown options, some people asked me (begged me?) not to do it so as not to bloat my little addon. Personally, I wanted the cooldown options so I decided to upload and maintain the original version as the light one.

So if you want merely a simple way to access your (trade)skills go for SkillsPlusFu (Light).
However, if you want the full monty stick with SkillsPlusFu.