Making a grinder - basically, it turns ores into dusts (not original, deal with it), but anyway, it smelts fine and whatnot (not changed it from the furnace code) but there is ONE thing I cannot figure out: 
  
The progress bars don't update. 
  
Here's the GuiGrinderBlock.java code: 
  
https://gist.github.com/anonymous/cf9d3555889a9aa302d6 
  
  
And here's the actual image (for co-ordinates reference): 
http://puu.sh/8tGzs.png 
  
It's 256x256 and I can't see what my issue is. 
  
If you need any more code, please ask and it'll be provided.