I went through the manual and read every word I could find about the click, and noticed it says:
After you customize your default click patterns as desired, Digital Performer will automatically use them whenever the click is enabled and your sequence Conductor Track matches the meter and tempo of each default click.
So I turned on the conductor track, inserted the Tempo event at 1|1|000*. Didn't work. So I added a meter change as well. Now the click defaults kicked in. My sequence was already at 4/4 80bpm.
The part that confused me, is that even if I switch back to the tempo slider, the conductor track still triggered the click defaults or click value, even if I changed the tempo slider...
Am I missing something here, or is this perhaps a bug?