Thanks to kholt for sharing the information on such a feature in Denmark. I never heard of it before and guess it is unique. Last weekend I tried it and observed what happens in the FIS system: they do indeed file separate flight plans, so this is just a convenient service and they do your labor to separate them. I don't think it makes sense to support this little step and focus better on more important things. Just my5cents.

As far as we are aware, there is no such thing as a multi-sector ICAO flightplan. As an international product we couldn't accommodate a nation-specific extension to the flightplan format, sorry.

Hi

I like the new multileg feature, but miss the possibility to file multileg ATS flightplans (FPT). Will this be made possible?

I understand that it may not be possible in all countris, but it is in Denmark. Having to file 3 flightplans for a 3 leg flight makes it costlier but also more time comsuming. FPL's are described in this document on page 30 and following (only in Danish, unfortunately). Page 31 holds an example of a FPT with 2 stops underway. 

http://aim.naviair.dk/AIM%20Documents/Vejledning%20vedr.%20flyveplaner%20og%20ATFM%20TACT-meldinger/Vejledning_FPL_TACT_31JAN2013.pdf