Probably depends on the host, but I have certainly had problems with Cubase from small changes like that.
I can understand that a new parameter would have an undefined value, but Cubase (maybe others?) just seems to get very confused when re-loading an old song after the .dll is updated, unless the preset structure is identical in order and size.
You can kind of work-around it by saving the presets as a text file before updating the .dll - and then re-loadng them after the update (doing the file save/load from the plugin GUI rather than the host preset handler) - that seems to work better, only the 'new' parameters are then left without values.
This issue doesn't just affect SM - there have been developers of big commercial synths who have had to provde "preset convertors" in the past, to allow back compatibility of presets with older versions.
Another solution is to only use the same 'Four letter code' for bugfixes etc. But to use a new code number when doing a big 'new features' release - then users have the option of a 'parallel' install, so that they can still keep the old version if they prefer. I have a sub-folder of my VST plugins called 'Legacy' that I keep old plugins in, just so that I know old projects will open exactly as I left them, even if they are years old.
Feel free to use any schematics and algorithms I post on the forum in your own designs - a credit is appreciated (but not a requirement).
Don't stagnate, mutate to create. Without randomness and serendipity the earth would be just another barren rock.