Hello! I’m fairly new, still learning Dorico. I don’t know if it’s because I’m using the SE version, but when I cast off say 4 bars per system, when I want tighter spacing in some places, there are no System Break flags I can delete. I checked that the signposts are visible. If I cast off using say 8 bars per system and add my own system breaks, those flags do appear (but this is cumbersome, especially without the keyboard shortcut). Am I missing something?
Secondly, is there a way to cast off starting/ending from somewhere specific instead of having it apply globally?
Thanks.
As I understand-
When you enter a cast off value in setup mode, no system break flags will show - the casting off is done under the hood, so to speak. You can still use “make into system”, but on a one system by one system basis. There is no way to choose a region and specify a different casting off value, that I know of.
It would be really nice if one could manually cast off an instrumental part on screen, using shortcut hotkeys (like Finale). Many copyists/engravers use the system described by Clinton Roemer in his “Art of Music Copying”. That is, each system starts at the beginning or middle of a musical phrase; rehearsal marks, segnos, repeats, etc. are always placed at the beginning of a system. However, rarely does this correspond to casting off a global amount. Some phrases will have irregular lengths, 1st and 2nd endings take up extra measures, notey measures throw off ideal casting off. It is not possible to find note spacing settings that do this automatically - manual intervention and a little old fashioned elbow grease are required. The manual intervention just needs to be made more easy.
Yes, what you’re describing in terms of when to start systems is exactly what I’m going for. So basically if you decide to cast off, you have zero flexibility in terms of adjusting them - you can only manually add new breaks but not remove any of the ones created by the cast-off? That seems… less than super useful. 
You’re more limited in SE/Elements than in Pro, at least as things stand. If you’re working in SE your best bet is probably to not use fixed casting off (in Layout Options), but set the top value in Layout Options > Note Spacing to something slightly smaller than optimal, then throw in extra System Breaks (from the Edit menu) when you need to.
I see, thanks.
Are casted-off system breaks shown/deletable in versions with Engrave mode?
It’s not that they’re deletable, it’s just that you you can tell one break to wait for another break (and there are Make Into System and Make Into Break buttons that speed up this process), meaning that you can override the fixed casting off.