I have investigated your issue and managed to reproduce it (after setting Windows to the Polish locale). In my case, the inconsistency in the presentation of the date separator in the export script was due to all the date formats in Preferences (please see prefs.bmp) using “-” as the date separator.
I have a workaround that you may be interested to try…please set your date seperator to “/” as I have done in my attached screenshot (regional_options.bmp). This should cause the list of date formats in Preferences to have a mixture of “-” and “/” (eg. “7/17/06 (MM/DD/RR)”, “17-lip-06 (DD-Mon-RR)”). When you do an export, the presentation of the date separator should be now consistent.
So do let us know how you go with the workaround, thanks.
FYI, we will be investigating the possibility of making the date format selector in Preferences editable in the future (which will help resolving issues like this).