Yes, the RKE requires the APC module to run Tunzes.
The programming for the Apex is not too difficult at all. You need to set up profiles, a profile being something like alternating between 2 pumps at 30 and 100% every 30 seconds. All of that is preset menus where you fill in times and percentages, always keeping the minimum above 30%. You would then just set that profile onto the appropriate connectiosn(V1/V2) would be one of the channels. If you wanted to do multiple profiles for different flow at differernt times, you just set the profiles to certian times, like "if time is 04:00 to 08:00, then profile 1.
Roger, the Apex and RKE put out 0-10V signals, do I recall right that there is an upper limit of 8 volts that should be the maximum supplied to Tunzes? Meaning that you woulld set the Apex controller at 80%, and that would be 100% on the pump?