How can I install PD8 on a external Drive?

Hi all.
I'm trying a new external drive, a 128 SSD via Thunderbolt, with my iMac 27 and 10.8.2.
I want to copy Parallels Desktop application on it, but it seems to be impossible. Installer does't ask me install location, and OS doesn't me able to copy App, because it said that I'm not enought privileges (!).

Can someone help me?

 

Hi Matteo,
just use sudo option in your Terminal:
sudo mv /Applications/Parallels\ Desktop.app /Volumes/[your disk]

 

Ok, it works. App translate to my external disk fine.
But after this, if I try to open it, OS copy it to my Startup disk again and open it (again) from my Application folder.
What the hell...

 

Ouch. Could you do the following for us:
0. Ensure you use the latest build of PD - 8.0.18345
1. Move the package to your external disk
2. Try to start it from external disk
3. Wait for that copying thing to be finished and Parallels Desktop started from whatever it wants
4. In started PD go to Help menu, send us Problem Report as described in http://kb.parallels.com/en/9058 and give me an ID.