Ok, if I've read both of your post's right. Your guys go to zone and by the time they pop up on the other side they have gone Link Dead and EQ close's out. Since we are not getting any kind of error message from either EQ or MQ (Or from Windows) it's safe to say that this isn't a crash. It's a disconnect.
So lets start with some Easy fix's and see if we can clear up your issue.
1. Reboot the o'l Computer.
2. Reboot your router and modem. (Full reboot here too. So unplug them for at least five minutes)
3. Do a dns flush. ( I think we are getting to the point this won't be needed anymore but I've seen reports it improves ping rate which can cut down on Link Death)
4. If you leave your toons loaded into the game 24/7. Make sure you restart EQ before you head into a heavy play session. (We've got memory leaks all over the place and instead of trying to figure out which one is getting you.. just restart the game.)
5. ON that note if you leave your computer up 24/7 or worse in Sleep mode. Make sure you do a quick reboot before you sit down for a long play session.
6. Check your power settings if your using a Laptop to keep windows from parking cores or putting other elements of your computer to sleep and destabilizing things like EQ.
Here is another thread with the same issue where Sic drops some real pro tips. I'd check it out:
still randomly occurs, happens on toons running KA and also on some running CWTN. Just happened now entering guild hall with 6 toons and 1 KA and 1 CWTN crashed.
www.redguides.com
Some other stuff.
Here lately it seems EQ is sucking up more and more resources to do the same thing. So, tweeking frame limiter may help. I don't have a thread handy but I know there are a few here at RG that go over the gritty details and could be of use.
If you try those things and still experience the crash's we'll need to dig a little deeper and ask a bunch of boring questions.