I seem to remember there being a macro based met spammer somewhere around the forum...
With it being click based though you'll need access to a edited conquer.exe to block their auto detection (as far as I know they are all paid now ahah) as well as trusting a click based bot (eew
)
past that though... I think the new encryption is still somewhat private so all the public proxy frameworks are down (both of mine, impulse's and fangs are all old encryption).
Your options are either clickbased ones or using hawtness' hook based framework to write a system to do it yourself (bit of work as cyanogen said but it's really not that difficult... like 3 packet structures, few memory hooks and some data collections to keep track of your inventory contents)