I have isolated one problem.
Step to reproduce:
1- I had an audio track with multiple sections in it and multiples vst added to the track.
2- I transformed this track to audio - to merge everything and save CPU power
3- I had to go back to the original audio so did the inverse process ad transfer back the audio track to it's original state.
4- The files created from the reverse conversion were multiples short clip overlapping each other on the same track. I did not notice at first. This track was causing S1 to crash. So I carefully cleaned the audio track of all the small duplicates overlapping each other and the crashes are gone...
Conclusion: many audio clips overlapping each other on one audio track will make S1 4.61 crash.
I took an great deal of time creating a project template with complexe routing (Buses, effects sends, VCAs...) And I can't use it! I have started a new song using my template and it crashes every minute or so... I'm trying to go here: http://download.presonussoftware.com/studioone/
To revert to and older version of S1 but the link os offline...