I just flashed Xposed Unistaller, booted and K-setting, installed but still can't access the Xposed Settings.....
Okay, that means Xposed is already installed, but you cannot manage modules because you have no access to the Xposed Installer (Manager)...
That's strange.
The other thing is, if you got with TWRP the Error:
Fork() process ended with ERROR= 255 before flashing the Rom - the whole installation is corrupted.
May you flash the Rom again. If you do, do it with this steps.
First flash Uninstaller of Xposed. After reboot TWRP with Main Menu "Reboot" Reboot Recovery. After go to wipe and use Advanced Wipe. Check Dalvik, Cache, data, system.
After flash the Rom again.
You said, its Classic Edition, right?
Check MD5 at first! Check it also with Mixplorer on your SD /characteristics/hashes
May your SD is corrupted.
But before flashing Rom again you can do following:
Go with Root Filemanager to: /data/data/de.robv.android.xposed.installer/conf/
and delete there "modules.list" - if it is present.
And after in every case boot to TWRP, go to Advanced Wipe and check only Dalvik/Art and Cache. Reboot needs about 10 minutes
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