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!
I can attest that these changes do make the bot work better. Before, when I clicked on "chart" it wouldn't show anything, just a blank screen. Now it actually works and things seem to be running more smoothly. Thanks for delving into this matter.
EDIT - One thing I noticed in the console, almost every line says "TypeError". What does this mean? The bot works fine but in the console I just see this a lot.