Here's a (very
brutal, indeed) fix for everyone having issues with v0 gox apis: v1 work very well indeed!
You need to change the following lines in background.js:
Line 128:
req.open("GET", url);
becomes (preventing chrome to use cached pages)
req.open("GET", url+"?sid=" + Math.random());
Line 271:
var url = "https://data.mtgox.com/api/0/data/getTrades.php?Currency="+currency+"&since="+since;
becomes
var url = "https://data.mtgox.com/api/1/BTC"+currency+"/trades?since="+since;
Line 283:
var trs = JSON.parse(req.responseText);
becomes (quite
raw, but it works!)
var trs = JSON.parse(req.responseText.replace("{\"result\":\"success\",\"return\":","").replace("]}","]"));
Line 304:
url = "https://data.mtgox.com/api/0/data/getTrades.php?Currency="+currency+"&since="+since;
becomes
url = "https://data.mtgox.com/api/1/BTC"+currency+"/trades?since="+since;
The bot is behaving MUCH better now thanks to the new apis

EDIT: probably the big issue was Chrome using the cached content, which stopped the bot any time it went through an empty page. With the line 128 workaround (above), v0 apis should work well, too!
Hmmm - I just got API v2 working here BUT there's a bit of a problem fetching trades with API v1 and API v2 - MtGox will return 1000 trades instead of 100 (with API 0), so the data traffic will increase 10-fold (and it will update
Unfortunately there doesn't seem to be any parameter to specify how many trades we want to fetch (we only need ONE sample for each interval!) The docs for API v2 is quite limited however - anyone know if there's a way to fetch single historical trades using API v2?