It was just an oddity. I went back and confirmed it's Ace 1.3 and AH_Wipe R10 so it shouldn't be a version mismatch. *shrug* in practice it makes no difference since I don't know anyone who only uses two addons. I was trying to see if I could recreate Maahe's problem as described... so I thought I should mention it. :)
Just to confuse things:
AH_Wipe + Ace: no button on first opening AH. The second time and later it shows up fine.
AH_Wipe + Ace + KC_Items: shows up ok.
AH_Wipe + Ace + LuaSlinger (with blank script, event on AUCTION_HOUSE_SHOW): shows up ok.
And now for something totally different... err I was able to log on finally. Reset button is not near the Auction frame (though it does work) and does not disappear when the Auction frame is closed. Ace 1.2.5 installed.
the button remaining was mentioned previously but I wasn't sure if the position info (above and to the right of the frame) would help any.