Jose, what version of CrossOver are you using? (I know you're a new customer, but if you bought a boxed copy at a store, it might have contained an old-ish version.)
You can download the latest version from here.
Programs running under CrossOver should respect the regional settings of Mac OS X. Those can be set in System Preferences > Language & Text (formerly International). Make sure both the Language tab and the Formats tab reflect your preferences. (The "Region" pop-up menu on the Formats tab must use one of the built-in presets. CrossOver doesn't fully understand custom formats.)
EDITED to add: For support requests like this, you should use our support ticket system. It's fine to ask questions in these forums, but you have no guarantee that one of our support staff will see it here. The ticket system helps us keep close track of issues like this and get you a definite prompt response.