Correct, that is not possible.
A Program is a combination of Preset A and B. You can use a combination of Chorus and RingMod as a Program, but you cannot combine them to be a single Preset.
Many of the algorithms can be used for multiple effects (ModEchoVerb, SpaceTime, etc.) so you can achieve more than 1 effect type using a single Preset.
If you follow my instructions from the last response, you can create a Program that uses a Sculpt Presets and a Weedwacker Preset.
