K5 Help : Remove GUI-Launcher before update ?

Hi,

*edit: Is is a Kindle Tocuh WiFi - so it is Kindle5*

middle of 2012 I have jailbreaked a kindle touch (5.1.0) with website ( jailbreak-kt.tk ) or something like this. After installation it was possible to install usbnet and GUI-Launcher and launcher-addons (sokoban,term,new reader) also from this webside 'per klick' - without any PC.
Now I want to remove these addons and the GUI-Launcher to be prepared for an kindle update. But I do not have files for uninstalling.
There is no menu item to detect installed versions of this additional stuff.
So I have these questions:
(1) Howto uninstall GUI-Launcher addons ? (but no zip-files avail)
(2) Howto uninstall GUI-Launcher itself ? (but no zip-file avail)
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(3) Howto detect which version of GUI-Launcher is installed ?
(4) Howto detect which version has the usbnet jb ?
(5) Is it possible to 'update' the usbnet jb with a newer version ?
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(6) Is it possible to use 'nearby' version-zip files for uninstalling ?

Thank you
- I hope it was not describe'd to cryptic -
br
walter