Never had that, sorry.
I never connect to any server that shows a ping (check several times with VROC's
refresh button) much over 300ms. And although I've had a few reliable sorties onto
low bandwidth servers, ADSL or Cable are by far the most reliable. Lesser
connections only seem to be good for two or three drivers most of the time. So if you
connect and see any signs of stuttering (usually when other drivers join or there's a
crash) do yourself a favour and quit before things get more unstable. IME a good
server to which you have a good connection (the two don't go hand in hand!) never
gives any signs of instability. Other drivers may disconnect and reconnect (showing
they have a poor connection to that server's "geographical" location) but if you have a
good connection you won't share their difficulties.
Never had that happen either, except when GPL crashed... which hasn't happened to
me recently.
I use the default 4.
I see you're already running with minimal graphic options to keep the frame rate up,
so you're doing what you can there (can't do any harm!) The only other thing is to try
another ISP. I found a Freeserve account works quite well with VROC. But basically
it's good to have an alternate ISP to try in case -- as past networking experience
shows -- it's the ISP at fault as much as any other part of the equation.
Andrew McP