Kevin,

The box you see is a non-printable character, probably a CR or LF (CHR(13), CHR(10) respectively). This character is most likely being appended to the string by the spell checking routine you are calling. You can fix this by trying this change;

* The following line removes any CR and/or LF from the string
gcText = StrTran(STRTRAN(gcText,CHR(10),""),CHR(13),"")

IF this.Enabled AND !this.ReadOnly
  IF this.SelLength > 0
    this.SelText = gcText
  ELSE
    this.Value = gcText
  ENDIF
ENDIF