Would appear so. 502 errors are when there is a trouble communicating between you and whatever web server you are trying to connect to.
http://www.checkupdown.com/status/E502.html" A server (not necessarily a Web server) is acting as a gateway or proxy to fulfil the request by the client (e.g. your Web browser or our CheckUpDown robot) to access the requested URL. This server received an invalid response from an upstream server it accessed to fulfil the request.
This usually does not mean that the upstream server is down (no response to the gateway/proxy), but rather that the upstream server and the gateway/proxy do not agree on the protocol for exchanging data. Given that Internet protocols are quite clear, it often means that one or both machines have been incorrectly or incompletely programmed."
Right now though it's timing out with a 404 error so it's likely userscripts either crashed again or they took it offline unexpectedly.