Actually you CAN register it on multiple computers at the same time as long as you use the SAME registration info on each one and you use the same Interlink.

This does not violate the EULA ( according to Knifeedge ) as you are still limited to running the program on one machine at a time.

KE states that they do monitor registration/installations and will disable accounts that are being abused.

I have RF installed on four different computers and all receive updates w/o problems.