Stoic Joker, how dare you to not send me an export if your settings xD ... could have been a major problem...
Oops... Sorry, I actually just assumed the issue was on my end.
Though none of the changes were related or should be related to the clock format...
O_o Okay, that is weird.
Anyway.. what kind of test build are you talking about? Your own or mine? I though you were using my version before...
Yours, Mine, LonelyPixel's, and some other stuff that may/may not be relevant. Honestly I don't remember if it was the home or office machine it happened on ... But both have been used for testing in the past.
P.S. by "blank" you really mean it? Please go to options and change font color to transparent, did it look exactly like that?
Text was completely not visible, and any attempt I made at getting it to appear failed. But the window size/shape implied that the format was intact, it just was the same color as the background.
Time - as usual - is not my friend...but I can try to reproduce the issue if it will help. But if nobody else reports that type of odd behavior...it was probably just me.