for us non-americans, can someone please explain what general political aims the 'moderate' and 'progressive' parties represent? And where are they on the republican democrat spectrum?
It's pretty hard to say what the terms "progressive" and "moderate" mean in a US context, but I would say that both terms exclude the American far right and populist movements, and are vague as to what they include otherwise. The Overton window has shifted hard to the right in the United States, so it's probably somewhat right of what you may expect from, say, a European perspective. A moderate will probably be sympathetic to limiting immigration, for example, a progressive is likely more in support of immigration. Both groups probably support minority rights (e.g. LGBTQ, Muslim, etc), but moderates less so.
In terms of economics, both terms and parties generally describe liberal capitalist economic policy, which is dogmatically entrenched across the US political spectrum, to the point where most Americans cannot conceptualize economic systems other than liberal capitalism. The main difference in political economic values across the US political spectrum fixate mainly on who pays how much taxes, and subsidies for liberal capitalist businesses. Progressives may be more pro-union, whereas most moderates are generally not.
Moderate and progressive groups can overlap, particularly in a politician who wants to appeal to both, usually by contrasting themselves with the right.
Disclosing my biases: I am an American leftist (or social democrat, if you prefer) living abroad, and I generally have quite a lot of disdain for moderates, particularly in the United States. I'm definitely holding my punches for this comment, though, for what it's worth.
Economically or socially and over what sort of time scale?