Ok Thanks for replying! I had read your article during this process but only the sake brewing part not koji article. Thank You!
So here is what i did. I steamed the rice in a metal strainer over a large pot of water, only a couple inches. Strainer was completly submerged in pot but not touching water. Covered with a towel to allow to steam. I steamed for an hour and rice was white not transparent but has the consistency of whats stated in your article.
First batch never developed spores, which i think was due to low temperature. Started a second batch 2 days later and used a little more koji spores and warmer temp in the cooler. The rice did start to develop white fuzz but was not completly covered. So i left it in for a couple days monitoring its progress and it seems like it went from mostly covered to covered in yellow green spores that exactly match your pic of tane-koji. Which are the only acceptable colors other than white. Its slightly moist still though.
Can it be used for sake? or should I make another batch? can this green spore be used make further batches?