Basically when you have a lot of columns(more than 10) in plan mode in rapid board of GreenHopper, then the user stories become unreadable and the user interface will be out of shape.

Steps to reproduce:

1. Create a scrum board
2. Configure the board to use Greenhopper simplified workflow and create more than 10 status and 10 columns
3. Allocate backlogs into a sprint and start the sprint
4. Go to Plan mode and you see something like below:
   

Besides, the Greenhopper wallboard gadget is affected as well: