ZELIO from schnider & FBD

I worked on zelio relay from schnider at FBD but I noted somethings :

1- there is no any marker relay ( internal output relay ) at FBD although there is 28 marker relay at LAD , why ??

is all FBD prgramming language from anther companies also as schnider did not contain any marker relay at FBD ??

2- I did not found any lamitation of numbers for timers and counters and for any blocks at FBD but the number of timers and counters at LAD are limted by 16 timers and i6 counters , why ??

is all FBD prgramming language from anther companies also
as schnider have no lamitation of numbers for timers and counters and for any blocks at FBD ??

thanks

i did not receive any answe for these questions ??

thanks