Doable but impractical. Without coding experience that side of things is going to be pretty daunting; the hardware hackery won't be easy either.
The most basic Arduino (a small footprint one, like the Micro) could handle this. You'd need to unhook the DD5's pots and route them into the Arduino's ADC, then have the Arduino control a 4 channel digital potentiometer with the DD5 pots, each channel taking the place of one of the original pots. You may get some undesirable audio artifacts depending on the digipot's specs. I'm pretty sure Chasebliss uses vactrols and PWM rather than digipots for their effects, but I don't think you'd need to do that here.
The toggle switch would also hook into the ADC; I'm not sure how the high-cut mod is implemented but having the micro open/close switching FETs connected to the caps might work.
Presets are a matter of saving and recalling the desired values from the EEPROM.
With some additional work you could even add a tempo LED, subdivisions and tap functionality, but it might not be 100% accurate.
Look up Arduino tutorials on the basics, digital control, analog control, working with digipots and EEPROM to get an idea of what you're getting into.
aka leaves turn - engineer with DigiTech/DOD