It sounds like there may be some sort of incompatibility between AFX and SSAO. I wouldn't be too surprised since it's likely they both make changes to some of the same files.
For this reason we don't officially support installing SSAO into anything except a clean TGEA SDK. (As I'm sure you can appreciate, there are an infinite number of different add-ons & modifications that developers can apply that may be incompatible with our shaders in some way. It's very difficult to debug codebases where we are unfamiliar with what has been modified.)
However, I recall that some users have had more luck by installing SSAO first, and then AFX (no promises). If you're having Out of Read and Out of Write errors, pay special attention to any networking changes the two kits make. It can be *extremely* easy to introduce an inconsistency between packUpdate() and unpackUpdate().
Let me know if that helps,