FontLab and Arrow Key Adjustments


I am currently use FontLab 5.1.4 on Mac OS Yosemite. According to the manual and my preference settings, I'm supposed to be able to move selected nodes with arrow keys by one unit per "click." However, when I try to just tap an arrow key nothing happens. The nodes will only move if I hold down the arrow keys, which then they move appropriately. However, the necessity to hold down the keys is preventing me from moving them 1 unit at a time. I need to be able to just tap the arrow keys. Holding them down makes the nodes move too quickly. I have scoured the preferences, menus, the manual and internet for a solution, but to no avail. Any ideas?