Decimal Separator in Language Settings
Changing non-English macOS default settings for fractions can fix problems with read aloud and embedded web code.
For some users with different European languages the default language on macOS can affect how the mathematics is applied in CircularFLO. e.g. for audio timings or CSS scaling.
With the maths used in CircularFLO and EPUB we need to be sure we are using a decimal point (.) rather than a comma (,) as the separator for decimal numbers.
The first 30 seconds of this YouTube video demonstrate how to change this.