I haven't seen the instructions you mentioned, but higher temps are definately not good. Higher temps increase the action of the sulfuric acid, which means that the anodized coating dissolves faster. This dissolution increases the pore size of the coating, as you stated, but it is not good that the pores get too large. It dissolves the cell from the inside of the cell, weakening the walls and opening the pore so large that the dye will not stay put. It seeps out and the sealing cannot completely seal the top of the cell. It is one of the 'problems' with anodizing. Cells to small and the dye isn't absorbed...cells to large and the dye seeps out. Its a balancing act, and good dyeing is only accomplished between the two extremes.
There are a couple ways to handle the heat in this weather. Take a larger bucket and put the anodizing tank in it, surround it with water and lots of ice. You only have to get the temp down about 10-15 degrees, so it should take too long. Or, as you stated, put in the refrigerator for a while. In either case, you'll have to keep an eye on the temp, as lower temps can also cause problems (cells too small to accept the dye). I've run into dyeing problems at 62F, so you only have about a 10F range. 70-72F seems to be ideal.
You know the importance of the connection, but from the photos, it appears that in some of the pics, that some of the area under the squares took the dye, which would be indicative of a connection problem. Although, I may be misinterpreting the photos. Yes, the anodization does migrate above the level of the electrolyte. I've found it migrates about 1/2"-3/8" above the electrolyte.
I didn't have time to look closely at your numbers the 1st time. You anodized .11 sq/ft at .500 amps (equates to 4.5 amps/sqft.). I'd raise the current to .66 amps. This will give you a current density of 6amps/sqft. I've gotten slightly better appearance with 6amp density than with 4.5.
Your anodizing time should be fine. Anything between 60-90 min should give you 1/2 - 3/4 mils based on the 720 rule.
Even with all this, since you don't know what alloy aluminum you are using, you may still have problems.
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