version 3.7.12 tried retail beta and alpha all give same errors when a spell is cast - player cast bar

20x FontString:SetFormattedText(): Font not set
[string "=[C]"]: in function `SetFormattedText'
[string "@Quartz/CastBarTemplate.lua"]:108: in function <Quartz/CastBarTemplate.lua:76>
[string "=(tail call)"]: ?

Locals:
(*temporary) = FontString {
}
(*temporary) = "%.1f"
(*temporary) = 1.414000

and

1x FontString:SetText(): Font not set
Lua Taint: Quartz
[string "=[C]"]: in function SetText' [string "@Quartz/CastBarTemplate.lua"]:346: in function ?'
[string "@Quartz/CastBarTemplate.lua"]:145: in function <Quartz/CastBarTemplate.lua:143>

Locals:
(*temporary) = FontString {
}
(*temporary) = ""

This only happens when I use a font I've registered with libsharedmedia. If I switch to another font I don't get this error.