Rahalroxz I suggest you ask the NAA that issued your license. But would suggest that the licensed guys who are supervising your work can sign your logbook regardless of who issued their licenses. They are after all certifying under the EASA 145 approval.
Dashmemder their is no requirement for engineers to keep a log book. The logbook can be used to record your work experience for grant of initial license application, type rating and license reissue. But this can also be done in another formate. But it's not a legal requirement to keep a logbook. The only time I use the logbook it when I've done a type course and I need to get the rating put on my license. But with the changes to part 147 training you won't even need to do that.