Can you flash just the progress bars and not an entire theme?
If you mean change the progressbar in a theme to a different one ,then yes you just replace the progressbar.png in the zip with the one that you want, but then you will have to edit the theme prop, with the new progressbar settings.
"Toggle usb storage" and put your zip on sd.
Then go to "install from sdcard", "choose zip from sdcard" and click on your zip file.
Depending on what you've flashed a reboot after flashing is necessary. In case you have flashed a new theme just go to "tools" and "reload theme".
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