the reason she was showing up in the scene is because you used the change scene action & assigned her character to the start spot - via the new game button "semester"... you should have used the change to scene of character or the show scene/menu action instead.
The reason you couldn't interact with the character is because on mouse over/out you were just changing the mouse cursor icon & not the command. The command was still set as "gehen" which was only set for interacting with objects.
If you don't plan on adding a coin or icon/text command selection interface then I would recommend just using a single command button like the broken sword & runaway games. You can just change the mouse cursor icons on mouse over/out etc... much simpler than messing about with loads of commands.
check out this wiki page I have been working on for some examples & tutorials on the different kind of command interfaces currently possible in Visionaire Studio. I've not finished writing the tutorials for each of the interfaces yet, but the general explanations for each are on the main page I've linked & I've finished the tutorial pages for both the single command interface & the cycle command interface.
http://wiki.visionaire-tracker.net/wiki/Control_Interfaces