Does this look right?

This is my third grow, Grain spawn blue oyster grown on sterilized Straw. I boiled Straw, drained it and cooled it. I added a good amount of fresh grain oyster. Put it in a container with a closed lid covered it with a black bag and placed it on a 74* heat mat. Today I opened it and took it off the mat and next to a led grow light. this is after one week. it looks like a shiny film is on the middle. Last grow in a hamper it was light white growth with pins that I misted and got great oysters out of it. Hope photo explains it better than i do. Thanks for any help or ideas.

Hello! Such film (overlay) appeared because of evaporated water pooling on the top layer of the mycelium. But it's not critical for oysters and your fruiting block is fine.

I'd skip using heat mat for oysters (they feel good at low temps and within 60-80F).

And they don't need flat block with opened top layer, because in nature they produce fruits on stamps, not on the flat ground.

So, now I'd make 2 small holes in the lid of this box and close it -> it will pin and fruit trough these holes. Or cover the box with a few layers of stretch/food film tightly and make 2 x-cross holes. Mycelium will search for the air and pins appear around these holes soon :-)