Good job on building yourself a koji muro
On future posts, try to add some space (hit the enter key), as this makes your posts a lot more enticing. I'll just comment as I remember things, so not in a chronological order (sorry).
Your rice looks a bit greenish. I don't remember my koji looking green, you should probably check out for possible infections.
Rice are really good at soaking a lot of water out of the air, so a lot of moist is required. Either way, there is not really any reason that your moisture sensor says 100%, while your rice is dry - maybe return it?
I would try to use a different material for containing a water source, as your current material is terrible for transferring heat (with a different material, you should experience a huge increase in moisture).
I would love some higher res pictures, also if you have from the entire building process.
Keep up the good work and remember to share it