This sounds like a behavior that a few users who have migrated user accounts between Macs have experienced.
In order to resolve the issue, do the following:
First quit FastTrack Schedule.
1. Go to Applications > Font Book. Launch the Font Book application.
2. On the left side select All Fonts.
3. Scroll down the list of fonts until you find Arial. Check to see that the Arial font is enabled. If not, then enable the font.
4. Scroll down the list of fonts to see if other fonts that you use might also be disabled and enable them.
5. Quit Font Book.
6. Launch FastTrack Schedule and your fonts should work as designed.
Basically, you need to enable your fonts.