If you did a clean install why should there be a bt folder anyway? The bt sources folder gets created when you upgrade not by clean installing.
I look at it after actually upgrading to 14376 but the file also is there before upgrading as being the source for the upgrade. Maybe grumpee can explain a little more, because my interpretation of his statement: "the install.esd is not there after a clean install", is he clean installed 14376 by using an iso created of the published 14376 esd files in this thread and in that case there won't be an install.esd file till the next build gets downloaded.
At least we will see new feature. Not boring build like the SR1 earliest builds (Not the first build).
Since the RS1 release date is soon, we may see more builds than usual, i would say at least one a week.
Any body else waiting for an very long time at screen ready soon I have waited for 15 minutes and aborted