Gaming devkitPro on Ubuntu Error

[Blue-K]

First: No idea if this is the right section. I don't think it's related to devkitpro, so I thought I'll post it here. I searched around one hour, but didn't found anything, so I hope you can help me.

Ok, today I've had enough of always switching my PC for compiling revs. So, I read this awesome Guide, followed it Step-by-Step, and it seems that I've done everything right. Sadly, it only seems...I always get the same Error:
CODEblue-k@blue-ks-laptop:~$ cd '/home/blue-k/dop-iosmod-read-only'
blue-k@blue-ks-laptop:~/dop-iosmod-read-only$ make
Makefile:10: /opt/devkitPro/devkitPPC/wii_rules: No such file or directory
make: *** Keine Regel, um »/opt/devkitPro/devkitPPC/wii_rules« zu erstellen.ÂÂSchluss.
blue-k@blue-ks-laptop:~/dop-iosmod-read-only$ sudo make
Makefile:7: *** "Please set DEVKITPPC in your environment. export DEVKITPPC=devkitPPC".ÂÂSchluss.
blue-k@blue-ks-laptop:~/dop-iosmod-read-only$
What's wrong? It seems that during the first try, it hasn't any rights to create a file, so I used sudo, but then it won't work even more. I think the added

export DEVKITPRO=/opt/devkitPro
export DEVKITPPC=$DEVKITPRO/devkitPPC

in .bashrc won't work for root, that's my guess. But I have no clue how to fix this now...

Thanks in advance!