Register Date Import

Hi there,
Hope you all having a nice weekend, although here is raining (Porto-Portugal).
Only today did I notice that the members that were import using this plugin, the Wordpress registem the date form them 01-Jan-1970.
Is it possible to change this?
Because next week I will import all the otheres members, around 500 and it strange they will have a registration date preview to the existence of website.
Can you help, please?