Hello, I had some issues installing Adobe Flash Player recently, and also to run Chrome. Which was in fact not that difficult to do.
As i think i'm not the only one having these issues, i thought about making an How-To, and here i am.
for this how-to i'll assume you're a total noob like me. So it will be clearly explained.

So, this is how i'm gonna do :

1- Downloading and installing Google Chrome.
2- Downloading the new Flash Player Version
3- Installing Flash Player for Chrome

Let's get started.

1- Downloading and installing Google Chrome

First of all, open a Shell
And enter the following commands :
cd /root/Downloads

#If the directory doesn't exist, then create it :

mkdir /root/Downloads
cd /root/Downloads
We download Google-Chrome's deb package from a trusted website (Clubic.com <- I don't know if there is an english version of this website.) [And nevermind about the "francais" in the url, it will be in english]
For x32 OS :
wget ftp://fcf6c50fd9b31b581f7bdb0d18402dc9:1362064925@soft.archive1.clubic.com/soft/logiciel/google-chrome_google_chrome_25_deb_32_bits_francais_306914.deb
For x64 OS :
wget ftp://fcf6c50fd9b31b581f7bdb0d18402dc9:1362064925@soft.archive1.clubic.com/soft/logiciel/google-chrome_google_chrome_25_deb_64_bits_francais_306914.deb
So now, the file is stored in our Downloads folder.

We'll install it :
#For x32:
dpkg -i -R google-chrome_google_chrome_25_deb_32_bits_francais_306914.deb

#For x64:
dpkg -i -R google-chrome_google_chrome_25_deb_64_bits_francais_306914.deb
Google-Chrome is now installed, but if you try to run it, you will get an error that says you can't run Google Chrome as root.
We'll fix this:
Go to /opt/google/chrome and edit "google-chrome.sh" (with Kwrite, Gedit, or do it via a shell with ViM if you want)

Once opened, go to the end of the file you will get that line:
exec -a "$0" "$HERE/chrome"  "$@"

#Now add --user-data-dir at it's end.
#Now you should have this:

exec -a "$0" "$HERE/chrome"  "$@" --user-data-dir
Save and close.You are now able to use Chrome.

2- Downloading the new Flash Player Version

So we get back in our shell (or open a new one )

#If you use the same shell as for the step 1, then enter this:

#Our shell is now cleared, we can start

mkdir /root/flashinstaller && cd /root/flashinstaller
We've got now a folder to work in.

Let's download Flash Player from the adobe website:
wget http://fpdownload.macromedia.com/get/flashplayer/pdc/
And now we extract it :
tar -zxvf install_flash_player_11_linux.x86_64.tar.gz
chown root:root libflashplayer.so
chmod 0644 libflashplayer.so
3- Installing Flash Player for Chrome

Now that we've extracted the new version of Flash Player, we need Google Chrome to use it:
First, we need to create a plugin's folder and copy Flash Player in it.
mkdir /opt/google/chrome/plugins
cp -f libflashplayer.so /opt/google/chrome/plugins
We need now to tell Chrome to look for installed plugins, so we'll do as in step 1 and edit google-chrome.sh in the /opt/google/chrome directory
Remember the last line we edited ? We're gonna edit it again:
#At the end of the file, we had that line :
exec -a "$0" "$HERE/chrome"  "$@" --user-data-dir

#Now we add --enable-plugins at the end of it
#And you should get :

exec -a "$0" "$HERE/chrome"  "$@" --user-data-dir --enable-plugins
Save and Close, now to verify the version of Flash Player you're using, go to this page with Chrome :

You should have this :

Chrome is now using Flash Player 11.

Feel free to tell me if something is wrong or not explained correctly, i won't bite
Thanks for reading
PS: I couldn't post in the How-To section so i did it here