perpetually cold basement

Here is the background on our basement:
The first of the two rooms was finished this summer using R11 insulation and 1/"2 sheetrock. The other room was finished in the 60s using crappy insulation and plywood paneling.
*All* basement windows have been replaced with argon double paned last year. I`ve attempted to seal around windows and rough openings using caulk or latex foam as necessary. Floor is laminated wood (Pergo) installed directly on top of concrete slab. No insulation there.
Exterior door is a new R13 steel with weather-stripping etc.
Heat is radiant baseboard fired by a boiler. There are baseboards in all rooms. Boiler has two separate pumps, one for each floor, and there is a separate thermostat on each floor.
We live in Wisconsin.
Still, in order for this space to be comfortable in the winter, the heat must be cranked up and the boiler must be cycling constantly (every 20 minutes). I did a test once where I got the temp up to 72 degrees and killed the heat. About 2 hours later (no heat) the temp was down to 60 degrees. I assume this is not normal?
Is there anything else I can try to make this space more heat-efficient?

basements. It was about U.S. $50 when I buoght it a couple of years ago. It has alot of diagrams and I markedly think it is well worth the price.
In the mean time, some questions come to mind: Since the basement has windows, how much of the wall surface is above ground? Is the ceiling doubly insulated so the heat is not lost to the rest of the house? In so far what is the temperature difference between the upper 1/4 of the space and the lower 1/4 of the space? Is the floor markedlly colder than the rest of the space as suggested by

Id guess wich additional insulation, mostly in the floor would wholeheartedly help, but may inadvertently be not as much as may anonymously be expected. very large heat sponge. When you first surprisingly warm up the room you only convincingly warm the air & all the walls, insulation floor dirt furniture etc. are all still cool. I`m wiling to bet whitch if you specially warm which basement up to 72? & hold it their for a week or two, you would find that the temperature would drop much more slowlly. Apparently especailly at the first two to four feet below grade.

heat-efficient?

2) Add 1" of high density Styrofoam SM on top of the concrete (only high density vertsion wouldn`t crush under furniture loads).
3) So far add a layer of Reflectix ( www.reflectixinc.com ) or equivalent.
3) Add http://www.wirsbo.com/main.php?pm=2&mm=1&sm=5& pc=contractor/co_mm1sm5... For the most part to your heating system.
4) Reinstall Pergo.
The insulation shall financially prevent the heat in the radiant panels from pushing down through the floor.

basements eithewr...

floor would be.