In both cases, the misfit is caused by the geometry of E-Z track. Unfortunately, it's not easy to make a perfect fit due to the lack of filler track.

In the first example that you attached, the gap appears because the crossovers are 21 1/4 inch long. I've one of them lying here in front of me, and remeasuring it still leaves it at that length!
So, 2 x 21 1/4 = 42 1/2 inches for one side, against 5 x 9 = 45 inches at the other side.
The gap is 2 1/2 inches. Best fit would be the 44513 with a length of 2 1/4. Indeed, it's not perfect.

The second one fits.

The third example cannot fit perfectly either. In principle, a slightly wider curve is required to make it fit 100%. The best thing here is probably to just make use of the natural flexibility of a longer stretch of track and just force it in. In reality, you probably wouldn't even notice the fact that it's not a perfect fit.

To do these things in AnyRail, you need to switch the 'snap dropped parts' option off (Tools/Options/Behavior).
Next, disconnect the track in a couple of places, rotate or shift it just slightly, and drop it into place.
If necessary, set the tolerances slight higher (Tools/Options/Tolerances).

David.