Delay happened more severe on editing large size notes —that is, 5000+ words and 30000+ characters— and less severe on small size note —though it does happen as well, regardless of which device—. If you need to see which part of the document is causing problem, I'll gladly send the document.
TextNut deleted part of document without my knowledge, presumably while syncing document via iCloud.
I'm using TextNut on both Mac mini at home and my Macbook Air along with a iOS version on iPad and iPhone.
After I finished appeding to existing document, I quit the app and the alert saying TextNut is syncing document via iCloud didn't pop up, which normal does. When I opened the document later on the same device I used for appeding to document, appended part has vanished. I tried to restore it from previous versions but although it showed there is previous version of document, there was no changes made. I doubt I mistakenly deleted the document because all other part of document was there and only the part I wrote that very day was gone. It neither happened last two days —of course, because I've been using Sublime Text for taking notes and using TextNut only for cpy-pasting the created notes— not I could reproduce the symptom, so I'll post later if I have more clues.
This issue occurred at Macbook Air.
At first I thought the part went missing because Mac mini also was running TextNut, but it turned out that was not the case. TextNut wasn't running on Mac mini at the time part of document went missing.
battery hogging issue
Mostly happening on Macbook Air. Sometimes it possesses 20% of total CPU resource. It's one of the biggest reason I can't use this app while on battery on my Macbook Air. Never happened on Mac mini though.