Yea, in fact, I got news about it, I have the concept down, but the animations is the part I am having trouble with.
But I am sad to say the game I am making it for wants the system to be exclusive, but I will be more than happy to guide you in creating it!
Here, let me start it off by saying that there are three (most likely) different things that are changed.
And, you can assign a variable amount (1,2,3.. etc) to each picture on the thing (IE: cherries=1, sevens=2, bar=3... etc).
make some way to make them spin, then land randomly. how they land is how they will change the variables.
then, if the first one matches to the second, and the second matches the third, then they must be lined up.
then if they are lined up, and if the first one is a 3, then they must all be bars (in my example) which wins you say, 100 gold.
using that concept, you can sculpt your idea in whatever way necessary.
If you are good with events, then you should be able to figure it out. if you need any more help, ask (or if im to horrible at explaining things)