Okay... I just went back and looked and now realize that casting bars are the exception for my timers... they don't show tenths like the rest of the timers do. I've modified the code in the PTR beta... it will be in the next update.
In the meantime, if you want to twiddle it yourself, edit the file [
Interface > AddOns > nUI > Units > nUI_UnitCasting.lua ] and go to line 1014 to make the change I've highlighted in yellow here...
Code:
if cast_info and cast_info.active then
local pct = ("%0.0f%%"):format( cast_info.pct_time * 100 );
local max = ("%0.0f"):format( cast_info.max_time );
local cur = ("%0.01f"):format( cast_info.cur_time );
local lbl = cast_info.spell_name;