Any chance you can give some details about the game? I haven’t gotten to play this one yet but am very intrigued. All the subsystems seem a bit complex but the agent vs architect play sounds really interesting.
The subsystems are mostly just variations on the core extended task system. It's just variations on what counts as weapons, terrain, and proximity. Agent/Architect isn't called out in the rulebook, but is still very present.
The basics of 2d20 for Dune:
All tasks are rolled on 2 to 6 d20's...
2 are free; 3 more can be purchased with momentum or threat, and one by help.
You use a Drive and a skill summed to set the target number. If you have an applicable focus for the skill, your focus number is the same as the skill; if not, the focus number is 1.
Your helper's provided die uses THEIR drive and skill, not yours.
Each die is compared to the TN and the focus number. If roll <= FN, 2 successes on that die; if FN < Roll <= TN, one succeess. If roll = 20, complication. All bought dice checked.
Total successes reduced by difficulty; if still in the positive, success, and the result is also how much momentum is there.
Momentum has other uses, too, such as extra answers on info tasks, extra effect on extended tasks...
If you want to be eased into the mechanics, the adventure in Heirs to Dune is really quite good. It's really a mini-campaign...