So I'm trying to set the project tempo from a stereo drum track.  I've enabled the Audiosnap on the drum track and all the transient markers look to be on the beat I'm trying to map.  However, when I click on the "Set project tempo from clip" in the Audiosnap dialog the project's tempo doesn't get set to all the beats even though I have the setting set to "beats".
 
The only beats that are matched in the operation are the transients that have been modified within the clip's tempo map (the beats that have turned red).  So a work around I've found is that I have to slightly modify each beat in the clip's tempo map so the beat count turns from black to red.  I can then perform the "Set project tempo from clip" and the project's tempo lines up with the clip beat for beat. 
 
I'm on the latest Sonar Platinum 2016.05.  Has anyone else had this problem?  I'm using this older method since I can't get the melodyne tempo matching to work that well.  The drums were recorded to a click track so the clip and project tempos are very close but I'm trying to improve it.   

If a beat marker isn't locked to a transient then it's basically 'free-floating' and will follow the tempo established by the nearest locked markers on either side of it so no tempo change is needed. This is deliberate so that if a transient is only off the mark by a hair, you can have SONAR ignore it and let the existing tempo run. This is good for performances that are basically a constant tempo with maybe few beats/measures/sections that are faster or slower than the average.
 
If you really want every beat right on the money, you need to 'nudge' each beat marker to get it to lock. I haven't worked with Audiosnap for a while, but I don't think there's any way around this.

brundlefly
If a beat marker isn't locked to a transient then it's basically 'free-floating' and will follow the tempo established by the nearest locked markers on either side of it so no tempo change is needed. This is deliberate so that if a transient is only off the mark by a hair, you can have SONAR ignore it and let the existing tempo run. This is good for performances that are basically a constant tempo with maybe few beats/measures/sections that are faster or slower than the average.
 
If you really want every beat right on the money, you need to 'nudge' each beat marker to get it to lock. I haven't worked with Audiosnap for a while, but I don't think there's any way around this.

In my case the clip's beat marker happens to be the exact timing as the transient marker.  The drums hit on the down beat of the clip's tempo.  But it shouldn't matter if they correspond or not.  The tempo and beat of the clip should be transferred to the project whether there's a transient or not. 
 
The issue I'm having is that the clip's beat and tempo isn't being applied to the project's tempo.  The only way I can get it to transfer is to slightly nudge the clip's beat so it turns red.  I actually move the beat slightly and return it to the original position just so it turns red and will transfer. 
 
I don't remember seeing this behavior with previous versions of Sonar.  Previously I would only use the clip tempo editor if Audiosnap had mistakenly assigned an adjacent transient the clip's tempo down beat. 

I just did a quick test and had no trouble. I got a tempo at every beat without locking any of the beat markers; I guess I was mistaken about having to lock markers to get them to generate a tempo change.
 
So now I'm not sure what might be going on in your case, but it must be project-specific. Maybe try Recompute Pictures for the audio file to reset transient markers and try again.
 
I stopped using Audiosnap for this purpose a long time ago when X1 (IIRC) introduced a bug that the tempo changes don't get inserted right on the M:B:T grid, which makes for really messy tempo map, though it generally sounds  okay. I prefer to use Set Measure/Beat At Now, which lets me set only as many points as needed to get good alignment, and puts tempo changes right on the specified beat (or fraction of a beat, which AS can't do and I often need).

Thanks for checking that out.  I'll see if I can get it working properly by importing that single drum track into a new project.

brundlefly
I just did a quick test and had no trouble. I got a tempo at every beat without locking any of the beat markers; I guess I was mistaken about having to lock markers to get them to generate a tempo change.
 
So now I'm not sure what might be going on in your case, but it must be project-specific. Maybe try Recompute Pictures for the audio file to reset transient markers and try again.
 
I stopped using Audiosnap for this purpose a long time ago when X1 (IIRC) introduced a bug that the tempo changes don't get inserted right on the M:B:T grid, which makes for really messy tempo map, though it generally sounds  okay. I prefer to use Set Measure/Beat At Now, which lets me set only as many points as needed to get good alignment, and puts tempo changes right on the specified beat (or fraction of a beat, which AS can't do and I often need).

Yeah in a new project with just this imported drum clip I'm still having problems. Half of the clip's beats are lined up to the project but the other half are off by anywhere from 30 milliseconds to 100 milliseconds. If you don't zoom in they look they're correct but they aren't.
While I was playing with the transients, portions of the clip and screen went black as my mouse passed over the screen. I had to restart Sonar to get things back to normal. I'm on version 1 of 2016.05. This has happened three times and it's never done that before so I think I'm done with Audiosnap as well.

Sounds like you might be having some problems with Audiosnap's late placement of transient markers rather than - or maybe in addition to - getting beat markers locked in. The new algorithm in Platinum has not opened to rave reviews. Because of this and the tempo-change placement issue, I think AS in X3 worked better in most respects. If you still have X3 installed you might want to generate the tempo map there, and bring it into your Platinum project by copy-pasting tempos.