unintended but good to know!
"F6-Set Next Praxis" sets the EXP for the next praxis point to 4990/5000, F7 adds 100 praxis points.
Actually, same thing happened to me last night when I downloaded the HF1 version. Nothing happened when I double clicked the trainer. So, I tried turning off my av and still nothing, then I simply restart my computer and suddenly it's working again.