Since release 0.9.7 APS has options related to authentication process.

For now there are AUTH_DEBUG and NTLM_FLAGS available.

AUTH_DEBUG:1 makes APS write detailed report on NTLM authentication dialog into *.auth
files in APS' working directory. Actually not very useful but it may be helpful for
understanding the NTLM authentication itself.

NTLM_FLAGS: some_hex_digits forces APS to use custom NTLM flags during the authentication.
For now it is known very little on their effects. So this option may be of use for
better understanding of NTLM authentication method.

NOTE: that flag format in NTLM_FLAGS is somewhat different from that in *.auth files
reported with AUTH_DEBUG:1.

NOTE 2: Looks like all this stuff will be useless without access to MS web or proxy server.