i just uploaded a new version of the wrapper : 1.1.1.2 get it here : http://acknexwrapper.matthias-auer.net
This version fixes a bug in engine_close()

get the C# wrapper:
for A7.85.4 and A8.30.4, Version 2.3.9
at http://acknexwrapper2.matthias-auer.net/ or visit the thread