You're right, it was not cleared enough. I just cleared this strip in Citrid Acid for five minutes. The result exhausted my patience to go through the complete procedure. Usually I would use Citrid Acid for the first bath, and EDTA+Sodium Sulfite for the second and third bath. Each bath five minutes respectively. But the problem is that the yellow stain would still be obvious even though I went them through the complete procedure.
The FeOx has been three months old since I received it from B&S. I know it's a bit old. But it still seems to work well in the uncovered part.
Thanks so much for the kind suggestion :-)
For pre-wetting the paper, I mean humidify the paper by holding it in the mist from a humidifier for few seconds. It's said to be helpful for reaching a deeper black, or so I have heard. :P
And there's one thing I can't understand. Should there be anything wrong with the paper, the solution, the tubes or the glasses, the part that was not covered by the Pictorico film shouldn't have reached its Dmax within 2 minutes in my first strip, and in totally dark too in the following strips with longer exposure time except for the four-hour one.