To change the clock font please change this.. refer to screenshot below.
To change the Startbutton please refer to screenshot below to import your own graphics into skinstudio. It best to name your new graphics with something else from the original graphics so you don't get confused.
Note : I saw few mistakes done on your mod. For example there is a mistake on horizontal taskbar background graphics. It should have only 2 state. Top and Bottom. You put it to be 5, which should not be. If you interested to learn there is tutorial on skinstudio on how to do things here : https://forums.wincustomize.com/447931/page/1/#3781427
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