I thought the Mem-clear do that...
Well, the my first version of NyanMem moved the swap sector, this involved modding the OS to look somewhere else. (Because people on IRC said you had to have one
)
However, that is not the case, my newer version just deletes the swap sector so you can use it as variable storage. It will come back as soon as you do something flash related though.
What happened to you was that you ran the first one which modded your OS. Then you left it that way and ran the second one. The reason you can't receive apps is because your OS is still looking for the swap sector in a place that it's not. So run the original NyanMem again, uninstall it, and you'll be good as new.