Stroeve ran up the stairs ahead of me, and when I reached the top floor I found him talking to a workman in his shirt-sleeves who had opened a door at which Stroeve had knocked. He pointed to another door. He believed that the person who lived there was a painter. He had not seen him for a week. Stroeve made as though he were about to knock, and then turned to me with a gesture of helplessness. I saw that he was panic-stricken.

"Supposing he's dead?"

"Not he," I said.

I knocked. There was no answer. I tried the handle, and found the door unlocked. I walked in, and Stroeve followed me. The room was in darkness. I could only see that it was an attic, with a sloping roof; and a faint glimmer, no more than a less profound obscurity, came from a skylight.

请教老师：Stroeve made as though he were about to knock - 怎么理解make as though 含义和用法? 在这里make是什么意思呢？这里的make是不及物动词吗？还是as though he were about to knock整个作make的宾语呢？

另外，no more than a less profound obscurity 是什么意思呢？