It seems to me, just a green beginner, (haven't even begun yet, just collecting information so far)...
... that your #2 picture is not possible with this theme as it currently is, or the element of the theme you're wanting to affect the change in.
It looks like, to me, that the picture #0, or the 'default' tcp panel picture is created in such a way that it can be tinted to a certain low percentage. Looks like probably 20% color fill for 'intensity' of color, or another way of saying it is that the pixels of the original are allowing a 20% transparancy to lay ontop of the 80% opaque panel (tcp panel).
And your #2 picture is wanting to color lay over at least 60% transparency color over and thus to have the original panel picture provide only 40% opacity. ??
Am I getting close to what is happening in here?
In other words, two things come to my mind; 1) find where and learn how to change the opacity percent in the config file.
or; 2) take the original tcp panel picture (png) file and lighten it 40% and place it in the directory and see if that then takes a darker tone of a color overlay on it.?
Trying to learn here.
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I tried editing some of these files. Unpacking the theme.zip file.
And I edited only the tcp#.png files.
It did make differences for sure.
I only worked in irfanview, not a paint program.
I increased drastically the brilliance and then drastically darkened the png files.
Or I just darkened the colors and then lightned them.
One image file in particular; 'tcp_mainbgsel.png' always made the most difference, in changing it.
So, there's a start anyway. A know nothing beginner's first steps and opinion anyway.