thanks for your patience, i'm using 1.5.2 and I if record SYSEX than try plying it, it works fine,
here's what i do step by step
-create a project
-check midi filtering settings (remove sysex flags)
-record sysex dump from my virus ;)
on one of midi track
-then change setting on virus
-play track from the beginning
sysex is sent to virus and its state restored properly
-save project
-start nuemdo
-quit nuendo
-play project from the beginning
virus state is not restored which is what i expected because sysex are not sent
there's an level meter for each channel (track) and that lights when track is played
but sysex is not actually sent
- I looked in the project browser and the sysex is still in there
Any ideas

Thanks for your help