Compared to Beta, this game has quite a bit more content. Maybe not a huuge margin more, but I'd say doubled at least.
You're probably logging in to the wrong Servers, either accidentally (likely) or intentionally. Be sure that the server you are logged on to is the nearest server available to where you live. Also, your connection to the server can be determined by pinging it. If you live in Asia or have a bad internet service, you're going to experience lag whenever you play ANY online game (And if you live in Asia, there are no servers for Asia in this specific game, increasing latency).
I have actually never experienced a bug in Spiral Knights, none at all, so elaborate please.
~Sev
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YOU CAN"T FIX THE LAG UNLESS YOU BUILD A NEW SERVER. WHICH COSTS A LOT OF MONEY. I think.
And what bugs are you talking about?