@Cecilia -
OK, it is a bit complicated to build something like a slider in SL1, but is possible. You basically create a series of horizontal line clips with a state for each that looks like the grab bar in a slider. At first the user only sees the horizontal line snippets and they are right next to each other so they look like a long line. The initial state for each is just a horizontal line. Then you create an invisible box over each horizontal line snippet that is a drag box. When that drag box is dragged over a horizontal line clip, you change the state of the line to be the grab bar state and the state of any other grab bar back to the horizontal line state so it always looks like there is only one grab bar on screen at any given point. This makes it seem like it is a slider bar. Then you have triggers which change a variable based on how many horizontal bar images you have. If you have three then you make the second horizontal piece count as 50(%). It is complicated and I don't have much time to write here but it does work. Here is an example of what our initial challenge base is with an SL1 slider working in it. Feel free to download and use it or adapt it if possible. Hope this helps!
http://elearninglocker.com/storyline_files/fun/slider_challenge/elearninglocker140027.story