You just need a compiler that's not ancient. gcc has been able to process utf-8 variable names since gcc 10. Clang and Visual C since like a decade ago.
I never got the jSON support to a finished state. There's extra stuff one needs, like put a button somewhere to activate it, document the format, some kind of dialog for choosing the filename to save to, an error message of the file can't be written, etc. Dumping all the timing data to json in way I can load into python and analyze it is only like 10% of the work. Something usable to someone who doesn't look through the source to find it and figure it out takes more.
A continuous center feature would be easy to do. One needs to understand the current center function means to center the most recent beat in the paperstrip. It doesn't look at the entire trace history and try to "best" center everything. Given that, it's easy to keep centered. It's actually far harder to do what I did to keep the trace from moving up/down as it scrolls while also allowing continuous zoom. It's more of a UI problem. Where do you put the button to turn this on and off? Next to the center button? Something in the paperstrip window itself like the zoom button? Another check box in the main menu, which is getting to be kind of long?
The default zoom level, 10x, is somewhat optimistic. If the watch is off by more than few s/d, you get traces that quickly go from edge to edge, like yours does about a minute in. You can zoom out so they don't wrap around so much and I think it's easier to see the changes.