You should be able to install it from Google Play, and you don't have to pay again, if you're logged in with an account that you already purchased it with.
The Android TV version has 2 extra screen layouts (portrait rotate right, and portrait rotate left), which you can select by pressing 'Screen Layout' in the radial menu.
Does that help?
It seems like some of your settings got messed up during the update. Did you make a custom screen layout for DKJC?
Can you try if you get video back by trying another screen layout, or resetting the current one to default?
DraStic has a warning popup if the device is running low on RAM and that it might close unexpectedly. I thought it could have been that.. If Android decides to close it immediately, you probably wouldn't be able to read taht anymore.
If those 3 files are copied there when you start, then DraStic can find and access the directory. If you then create a subfolder 'system' and place them in there with the correct name, it should find it. If not, it might not be the correct files.
Did the folder sdcard/Android/data/com.dsemu.drastic/files/ already exist when you placed them there, or did you have to create it? What error message do you get when trying to install?