In case anybody else is having the same issues: my client wouldn't start, being stuck at "loading configuration: 0%" and crashing in 30 sec or so with a message along the lines of "couldn't load configuration from the website, check your connection and firewall settings". Removing and reinstalling the client fixed it.
Also, for some reason the runescape website itself behaves like it is being ddosed or something: the forums load one out of 3 times, and I wasn't able to get into the tech support forum even once. Hope it goes away soon
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