I tried it this morning and no failures again. Right now I am thinking that I have a perfect storm of everything mentioned so far. I did stick a knife blade into the sear slot to see if the sear was centered. I could scootch to the right and left so if it is binding it is not extreme. It does have a little bias wanting to be to the left, so BRs first inclination of something touching the sear could be correct. I probably have a weak spring and can check it against the one just purchased from Whig. I had this thing apart and together so many times I probably forgot to lube the trigger when installing it the last time. Also I did not alter the sear in anyway, I can see some micro dings that should have been removed from the sear with a fine Arkansas hone. Also as discussed in the trigger modification thread I did not hone off any dings on the edges of the sear knuckle/hinge.
So right now the plan is to disassemble and look for all these obvious things, and reassemble correctly and hope there is not one more unknown we forgot. I looked for my small tube of gun grease and could not find it, that makes it kind of obvious I forgot to grease things doesn't it.
So it will take a couple of days to get some more grease, so that is more time to think more on this.

Got a question since the trigger was not catching the cocking piece that meant the opening cam for pulling it back was releasing it relatively slowly. How slowly does the firing pin have to be released so there is no hang fire or unintended ignition. Can you pull the trigger and let the pin down slowly enough that the pin will not dent the primer? Easy experiments to try with a primed case with no powder.

I did the check on the safety pulling the cocking piece off the sear. That was an early concern since this Krag has the bolt with the extreme wear on the lug. Everything was OK there. OOH, that is one more thing to check, make sure that in cycling the bolt it always comes back far enough to catch the trigger sear