i doubt this is the real solution, but here goes.
i did a full un-install of AHII 2.00.2 i had originally installed AHII then upgraded through the BBS here to 2.00.2
after the un-install i did a reboot, deletion of the full HTC directory, regedit and removed all HTC releated things i found, scan disk, defrag, and reboot in that order.
then installed AH 2.00.2 full from scratch. intalled mitsu sound 1.06 (i like it better than 1.07) and did a reboot.
then i started AHII and selected the "default" settings, went online then exited the game after about 5 minutes.
i rebooted, and then copied the JS and keyboard mapping *.cfg files into the settings folder, and re-launched AHII
all worked great. changed a few of the detail sliders, and my vid mem used never went above 80 (used to get up to 110) after 3+ hours of flying.
only problem i had the whole arena had.. the text buffer lag for a bout 5 minutes around 10:00 PM CST.
HiTech, is it possible something is getting corrupted in the "upgrades"?
all the other stuff i did was a bit over-zealous and just me being safe (to know it is nothing on my end causing problems).
well just my observations