Hi Isidro,
I am not with Laminar Research; just a flight simmer.
Are you running XP in demo mode? If you are you need to install the product key when and where asked in the "boot-up" process. If you don't, XP defaults to the demo mode and restricts you to a set location and a set time period. I understand you will get a lot of water visual.
If running in full mode ie not in demo mode, use the option to "check for updates". DONT tick the check for Beta option button. The installer program will run and will check for missing files and replace any corrupted files in the loading process.
Good luck
Glenn