A ".":"+1" for usage in a char count formula then using {quantifiers} to color the half of that number of chars in the inline options is not that complicated (only more verbose), but for strictly half of the string, keeping track of string length by chars is an impediment, since you can't color half of a char one way and the other half differently (I know, who would do that anyway?).Just FYI, there is really no easy way to determine "half" of a string, since Rainmeter doesn't keep track of string length by "characters", but only by "pixels". To count characters, you are going to need either a fairly complicated (Rube Goldberg'ish) Substitute option, or the use of a reasonably simple Lua script.
If that is really really desired, a solution using the String meter as a container meter along with a "contained" Shape meter with its halves colored differently (either as 2 different shapes or a "hard stop" gradient) might work. Something roughly similar to the 2nd example here:
https://docs.rainmeter.net/manual/meters/general-options/container/
Statistics: Posted by Yincognito — Yesterday, 6:15 pm