[Elephone P9000 ROMs, Kernels, Recoveries, & Other ] JBO0560:
Thanks for your fast replies but even after 30 minutes the device was still stuck in the bootscreen which seemed quite strange to me and the log files showed that several files weren't found and mount errors too :(

The log can be found here

AROMA INSTALLER version 3.00
(c) 2013-2015 by amarullz.com

ROM Name : DarkSense
ROM Version : 3.0.0
ROM Author : Jonny
Device : Elephone P9000
Start at : Tue Jun 28 11:29:51 2016

Welcome To DarkSense
For Elephone P9000
Developed by Jonny
Powered by Android 6.0
with
HTC Beats Audio

about to run program [/sbin/mount] with 5 args
mount: mounting /dev/block/platform/mtk-msdc.0/by-name/system on /system failed: No such file or directory
run_program: child exited with status 255
about to run program [/tmp/DarkSense/backuptool.sh] with 2 args
about to run program [/sbin/umount] with 2 args
umount: can't umount /system: Invalid argument
run_program: child exited with status 1
>>> Executing Super-Wipe Script

DarkSense Super-Wipe Script
This will erase ALL Data

about to run program [/sbin/sleep] with 2 args
1. Erasing & formatting EXT4 Cache partition
about to run program [/sbin/umount] with 2 args
about to run program [/sbin/mke2fs] with 6 args
mke2fs 1.42.9 (28-Dec-2013)
Could not stat /dev/block/platform/mtk-msdc.0/by-name/cache --- No such file or directory
The device apparently does not exist; did you specify it correctly?
run_program: child exited with status 1
2. Erasing & formatting EXT4 System partition
about to run program [/sbin/mke2fs] with 6 args
mke2fs 1.42.9 (28-Dec-2013)
Could not stat /dev/block/platform/mtk-msdc.0/by-name/system --- No such file or directory
The device apparently does not exist; did you specify it correctly?
run_program: child exited with status 1
3. Erasing & formatting EXT4 Data partition
about to run program [/sbin/umount] with 2 args
about to run program [/sbin/mount] with 5 args
mount: mounting /dev/block/platform/mtk-msdc.0/by-name/userdata on /data failed: No such file or directory
run_program: child exited with status 255
about to run program [/tmp/DarkSense/wipe.sh] with 1 args
4. Removing system files from Internal Storage

>>> All partitions wiped successfully! <<<

about to run program [/sbin/sleep] with 2 args
5. Now checking filesystems for errors
about to run program [/sbin/e2fsck] with 3 args
/sbin/e2fsck: No such file or directory while trying to open /dev/block/platform/mtk-msdc.0/by-name/system
Possibly non-existent device?
run_program: child exited with status 8
about to run program [/sbin/e2fsck] with 3 args
/sbin/e2fsck: No such file or directory while trying to open /dev/block/platform/mtk-msdc.0/by-name/userdata
Possibly non-existent device?
run_program: child exited with status 8
about to run program [/sbin/e2fsck] with 3 args
/sbin/e2fsck: No such file or directory while trying to open /dev/block/platform/mtk-msdc.0/by-name/cache
Possibly non-existent device?
run_program: child exited with status 8
about to run program [/sbin/sleep] with 2 args

DarkSense
Is now ready to install

about to run program [/sbin/sleep] with 2 args
>>> Installing ROM
about to run program [/sbin/mount] with 5 args
mount: mounting /dev/block/platform/mtk-msdc.0/by-name/userdata on /data failed: No such file or directory
run_program: child exited with status 255
package_extract_file: can't open /dev/block/platform/mtk-msdc.0/by-name/system for write: No such file or directory
about to run program [/sbin/mount] with 5 args
mount: mounting /dev/block/platform/mtk-msdc.0/by-name/system on /system failed: No such file or directory
run_program: child exited with status 255
about to run program [/tmp/DarkSense/backuptool.sh] with 2 args

>>> Flashing User Choices
>>> Installing GPS fix Europe

>>> Creating Symbolic Links

>>> Setting Permissions

>>> Flashing Stock kernel
package_extract_file: can't open /dev/block/platform/mtk-msdc.0/by-name/boot for write: No such file or directory

>>> Running ROM configuration scripts

>>> Enabling EXT4 Optimizations
about to run program [/system/xbin/busybox] with 4 args
run_program: execv failed: No such file or directory
run_program: child exited with status 1
about to run program [/system/xbin/busybox] with 4 args
run_program: execv failed: No such file or directory
run_program: child exited with status 1

>>> Installing SuperSU...
about to run program [/sbin/busybox] with 6 args
Archive: /tmp/DarkSense/SuperSU/SuperSU.zip
inflating: META-INF/com/google/android/update-binary
inflating: META-INF/com/google/android/updater-script
about to run program [/sbin/busybox] with 6 args

*****************
SuperSU installer
*****************
- Mounting /system, /data and rootfs
cat: can't open '/system/build.prop': No such file or directory
0+0 records in
0+0 records out
0 bytes (0B) copied, 0.000412 seconds, 0B/s
cat: can't open '/system/build.prop': No such file or directory
3+0 records in
3+0 records out
3 bytes (3B) copied, 0.000571 seconds, 5.1KB/s
cat: can't open '/system/build.prop': No such file or directory
10+0 records in
10+0 records out
10 bytes (10B) copied, 0.000609 seconds, 16.0KB/s
cat: can't open '/system/build.prop': No such file or directory
0+0 records in
0+0 records out
0 bytes (0B) copied, 0.001481 seconds, 0B/s
sh: bad number
sh: bad number
- Extracting files
Archive: /tmp/DarkSense/SuperSU/SuperSU.zip
inflating: META-INF/MANIFEST.MF
inflating: META-INF/CERT.SF
inflating: META-INF/CERT.RSA
inflating: META-INF/com/google/android/update-binary
inflating: META-INF/com/google/android/updater-script
inflating: arm/chattr
inflating: arm/chattr.pie
inflating: arm/libsupol.so
inflating: arm/su
inflating: arm/sukernel
inflating: arm/supolicy
inflating: arm64/chromeos/futility
inflating: arm64/libsupol.so
inflating: arm64/su
inflating: arm64/sukernel
inflating: arm64/supolicy
inflating: armv7/chattr.pie
inflating: armv7/libsupol.so
inflating: armv7/su
inflating: armv7/sukernel
inflating: armv7/supolicy
inflating: common/000000deepsleep
inflating: common/99SuperSUDaemon
inflating: common/Superuser.apk
inflating: common/chromeos/kernel.bootloader
inflating: common/chromeos/kernel.config
inflating: common/chromeos/kernel.keyblock
inflating: common/chromeos/kernel_data_key.vbprivk
inflating: common/file_contexts_image
inflating: common/install-recovery.sh
inflating: common/launch_daemonsu.sh
inflating: mips/chattr.pie
inflating: mips/libsupol.so
inflating: mips/su
inflating: mips/sukernel
inflating: mips/supolicy
inflating: mips64/libsupol.so
inflating: mips64/su
inflating: mips64/sukernel
inflating: mips64/supolicy
inflating: x64/libsupol.so
inflating: x64/su
inflating: x64/sukernel
inflating: x64/supolicy
inflating: x86/chattr
inflating: x86/chattr.pie
inflating: x86/libsupol.so
inflating: x86/su
inflating: x86/su.pie
inflating: x86/sukernel
inflating: x86/supolicy
sh: bad number
sh: bad number
- System mode
- Disabling OTA survival
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /tmp/supersu/arm/chattr: not found
- Removing old files
rm: can't remove '/data/su.img': No such file or directory
rm: can't remove '/cache/su.img': No such file or directory
- Creating space
- Placing files
mkdir: can't create directory '/system/bin/.ext': No such file or directory
chown: /system/bin/.ext: No such file or directory
chown: /system/bin/.ext: No such file or directory
chmod: /system/bin/.ext: No such file or directory
rm: can't remove '/system/bin/.ext/.su': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/bin/.ext/.su: nonexistent directory
chown: /system/bin/.ext/.su: No such file or directory
chown: /system/bin/.ext/.su: No such file or directory
chmod: /system/bin/.ext/.su: No such file or directory
rm: can't remove '/system/xbin/su': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/xbin/su: nonexistent directory
chown: /system/xbin/su: No such file or directory
chown: /system/xbin/su: No such file or directory
chmod: /system/xbin/su: No such file or directory
rm: can't remove '/system/xbin/daemonsu': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/xbin/daemonsu: nonexistent directory
chown: /system/xbin/daemonsu: No such file or directory
chown: /system/xbin/daemonsu: No such file or directory
chmod: /system/xbin/daemonsu: No such file or directory
rm: can't remove '/system/app/Superuser.apk': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/app/Superuser.apk: nonexistent directory
chown: /system/app/Superuser.apk: No such file or directory
chown: /system/app/Superuser.apk: No such file or directory
chmod: /system/app/Superuser.apk: No such file or directory
rm: can't remove '/system/etc/install-recovery.sh': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/etc/install-recovery.sh: nonexistent directory
chown: /system/etc/install-recovery.sh: No such file or directory
chown: /system/etc/install-recovery.sh: No such file or directory
chmod: /system/etc/install-recovery.sh: No such file or directory
rm: can't remove '/system/etc/init.d/99SuperSUDaemon': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/etc/init.d/99SuperSUDaemon: nonexistent directory
chown: /system/etc/init.d/99SuperSUDaemon: No such file or directory
chown: /system/etc/init.d/99SuperSUDaemon: No such file or directory
chmod: /system/etc/init.d/99SuperSUDaemon: No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: can't create /system/etc/.installed_su_daemon: nonexistent directory
chown: /system/etc/.installed_su_daemon: No such file or directory
chown: /system/etc/.installed_su_daemon: No such file or directory
chmod: /system/etc/.installed_su_daemon: No such file or directory
- Restoring files
- Post-installation script
rm: can't remove '/system/toybox': No such file or directory
rm: can't remove '/system/toolbox': No such file or directory
/tmp/DarkSense/SuperSU/META-INF/com/google/android/update-binary: line 1382: /system/xbin/su: not found
- Unmounting /system
- Done !

>>> Installing GorkMod...
about to run program [/sbin/busybox] with 6 args
Archive: /tmp/DarkSense/GorkMod/GorkMod.zip
creating: META-INF/com/google/android/
inflating: META-INF/com/google/android/update-binary
inflating: META-INF/com/google/android/updater-script
about to run program [/sbin/busybox] with 6 args
******************************
grork my p9000
made in Germany
by vsrookie
grorkmodinstaller v0.9
******************************
Archive: /tmp/DarkSense/GorkMod/GorkMod.zip
creating: META-INF/
creating: META-INF/com/
creating: META-INF/com/google/
creating: META-INF/com/google/android/
inflating: META-INF/com/google/android/update-binary
inflating: META-INF/com/google/android/updater-script
creating: arm64/
inflating: arm64/libsupol.so
inflating: arm64/su
inflating: arm64/sukernel
inflating: arm64/supolicy
creating: sbin/
inflating: sbin/grorkmod.sh
creating: su/
creating: su/bin/
inflating: su/bin/seinfo
inflating: su/bin/sepolicy-inject
inflating: su/bin/sesearch
creating: things/
inflating: things/grorksupport
inflating: things/initdsupport
inflating: things/policiesinject.sh
- Mounting /rootfs
- Mounting /system
Cant't mount system, abort.
run_program: child exited with status 1
about to run program [/sbin/umount] with 2 args

Finished... Reboot and enjoy.

First boot may take a while...

The DarkSense Official ROM

script succeeded: result was [1.0]

Installer Sucessfull (Status 0)

End at : Tue Jun 28 11:30:08 2016

EDIT : The Problems were caused by TWRP 3.0.0. ... the installation was successful by using TWRP 3.0.2-1 :)