the cream is called lac-hydrin. its available only through prescription in the US. you can also use an over the counter lotion or treatment with AHA (alpha hydroxy acid.) a good one is paulas choice 8% AHA. its about $8.
i still have KP, and i dont think it will ever go away. from what ive read, there is no cure. the only thing you can do is to keep treating it forever. some people have success with exfoliating with a loofah or shower puff. i dont see much difference, but my arms do feel less bumpy. it takes years for the scars to disappear, and by that time i just have new ones. lately, mine has been spreading to my forearms and lower legs. i used to have it only on my upper arms.
i find that it gets better in the summer when im in the sun more. i try not to tan outdoors at all, but when i do have a bit of a tan, the KP improves tremendously. im not really sure why that is.
im not sure if i mentioned this in the last thread, but KP is hereditary. my mom and brother have had it for as long as i can remember. my two sisters dont have it, though.