Not sure what you mean by rules?
All the MMO's I have played to date (going back 10 years now) have had the same setup as far as test servers go and that is that they are there to test things before they hit live.
Bottom line as far as characters go is they are not guaranteed but from my experience it's been extremely rare where they have been wiped but the risk is just higher on test then live.
Generally there are no events etc, wipes are only as a last resort and they have a lot more downtime then regular servers.
The plus side of playing on a test server is you get to see things before anyone else, feedback on them and make a difference on what goes to live.
The down side is that what always seems to happen is a small community forms on test that manage to somehow get themselves alianated from the live server crowd.
I've seen this happen in every game i've played and what seems to happen is 2 things, firstly whenever a 'bad' patch hits live then straight away some of the live crowd blame the testers for not finding the bugs (when in reality the bugs are found to late to stop the patch going to live and are fixed with the very next hot fix). This drives a wedge between the 2 communities. The second thing is that some of the tester crowd form some sort of exclusive club and think they are better then anyone else so when there is a sudden influx of live people trying something cool on test some of the regular testers go as far as forming private channels and going out of their way to not help those who came to test just to try the latest fad.
I'd like to think that this won't happen in Vanguard but have been around to long and seen it happen too many times to not be realistic.
Sorry am going off on a tangent here.
Rules,
1, Your character may be deleted / become corrupted and you may have to start again.
2, The server will suffer a lot of downtime.
3, There are unlikely to be the sort of events you get on live.
4, There is unlikely to be GM support for things like lost items etc.
5, The purpose of test is to primarily catch any bugs the internal testers have missed before it hits live, think of it as the last stage of beta for each update.
6, You don't have to test anything and can just treat it as your home server but you must be aware of the risks involved and not get upset if any of the above affect you in anyway.
I think that's about it, if you can live with all of those then you should have a good time
