At design time, I am simply trying to type in the option "V" in my combo list. When I do so, I get an invalid character block showing up. If I type in a space before the "V" (as in picture #2), it shows up fine. If I type in "mA" again without a space, it shows fine. It seems any time I tried to use a single character, I got the strange character block. Anyone familiar with this behavior?