Found the problem! For some reason my Sims 2 folder had become read-only. Windows is weird.

I am having a little trouble making my custom neighbourhood. All went well, and I imported my first 8 townies. I then generated NPCs. After that I creates more sims in CAS, and tried to turn them into townies. All seemed to go well, until I reloaded the hood. Only my first 8 townies were showing up as townies, the rest could be summoned by the inge shrub under the 'default' menu, but they were not in the Sim Bin. I can remake them into townies, but they always go back into the 'default' group upon a reload. I can't seem to commit ANY data to the hood now. A created sim will simply disappear and silently go into the 'default' group. Hood scenery will placed will also disappear after a reload. SimPe shows only the original 8 townies and NPCs. Is it Fubar, or savable? Could I put the sims I created into a fresh unbroken hood?

[EDIT]
I apologise, this is now occurring in all hoods, I guess it must be CC... any other ideas what it might be?