My method of Gunslinger Engie is not quite as aggressive as Gpop's or Molten's. It's used more as a supportive device directly in the front during a rush, or usually as a deterrent in a hidden corner to distract the other team and keep them pinned in an area (such as with the final CP of Gold Rush area 2 as BLU). I also don't bother picking up or refilling mini-sentry ammo - it's cheaper and faster to make a new one.
I don't do too well with this combination, but I'm not really an Engie player to start with (usually I go Engie as a helper unit in setup time or when the team is lacking one - and sitting back with upgraded sentries is too boring for me). But it does its job.
I still kinda want it, but how the heck do I trade with you in this game?
Inside TF2:
Items -> Trading. There you can use anyone from your friends list (provided they are playing TF2 as well at that moment), the current server, or any player whose Steam Community URL you know (though they'll need to get on TF2 as well).
Steam Trading:
Send a trade invite to anyone on your friends list provided they are online.
Uh, you said it was -dxlevel 80 before. :V (and it's what I have and it works)
I say use -dxlevel 81 first, then 80 if problems persist.
You know, if I was smart, I would've saved a replay of me killing you at the exact moment the gates opened up with a taunt. :getdown: That was just too hilarious.
People can and will do that on real matches, usually failing miserably of course. :V
I should've saved a replay of us tauntkilling each other at the same time...if that even happened. Gah, busy busy....
(for some reason though the replay editor crashes on my system)