There are a few levels that have been already fixed (the one where the issue was the most visible). But I think on some levels, there are still little differences.
In the 5-5, we wait less for the locks to disappear in the beta build, just before the end of the level.
In the 5-18, locks are slightly quicker in the beta build (less than a second I think).
Also I would add the 5-17, where the first auto-aiming rocket launcher seems to trigger a little bit earlier in the beta build. But I'm not 100% sure for this one.
Once again, there is nothing bad in these differences, but since it was said that this new build shouldn't modify the gameplay at all, I prefer to warn. Also they may just be linked to framerate being not exactly the same (and we do know that framerate can make weird stuff to happen in this game ^^).
Also, I want to point out that I think there was no difference between 1.2.4 and 1.2.5 on this topic (but my memory may be wrong)