It is geared toward younger kids, the games would be too easy for an 8 year old. I think all of them max out at 8 for the age range, (many are 4-6 year old, and some are 5-8). The game system would probably interest them for a few hours or days max.
They do not have any apps in spanish other then 4 Pocoya videos in the app store. They do have some apps in French. Here is a link to the apps on the Leapfrog site so you can check https://us.appcenter.leapfrog.com/storefront/leapster-explorer/foreign-languages/cLSTR,cLSTR_FRENCH,p0.html
Hmm... well thats a tough one as I cannot speak for other parents that have children with ADD, but I can say that the games, while fun for awhile, tend to get repetitive (i.e. same levels, different guys). I think I would probably veer more towards a product that has a large selection of AFFORDABLE games and activities, or just straight up go with a Kindle or other Tablet. Tablets nowadays come with pretty decent parental controls but will allow your little one the variety and freedom that she so desperately requires. If you are looking for something incredible, I would look at ABCMouse.com. It allows you, the parent, to adjust the level of learning for your child starting all the way at preschool. 2 of my children have now used it and wow, we would not look back. The price of 9 dollars a month (less if you buy a full year... which would be less than the price of this product and a few games) you really cannot go wrong. And the great thing is that you don't need an incredible laptop or computer to power it, just a basic (cheap) model with a mouse (optional, but I suggest getting her used to it) and an internet connection. Definitely check out ABCMouse.com, and good luck in your search!
We had that happen to us once but it was Becca's the game was not made for the leapster explorer but the leap pad. I would check and settee if that that is the problem. If it's not I think you can contact leapfrog and they could help.