Hello Everyone,
my first post - so please don't shoot me if it goes wrong!

I'd been looking for this for some time now and have seen a number of related queries but no solutions.

I cannot take credit for the whole code here, but I did adapt it to include the text formatting. The possibilities are endless.

Hopefully someone will find this usefull.
Good luck

void __fastcall TForm1::GridDrawCell(TObject *Sender, int ACol,
      int ARow, TRect &Rect, TGridDrawState State)
{

  //Affects the fixed cells - should there be any
  if (State.Contains(gdFixed))
  {
    StringGrid70->Canvas->Brush->Color = clBtnShadow;  //background
    StringGrid70->Canvas->Font->Color = clWhite;       //text
  }
  else

  //the currently selected cell is green
  //change this to the same colour as the background in order
  //to "hide" the selected cell
  if (State.Contains(gdSelected))
  {
      Form1->StringGrid70->Canvas->Brush->Color = clGreen;
      Form1->StringGrid70->Canvas->Font->Color = clBlack;
  }
  else

  //turns cell[2][2] yellow
  if (ARow == 2 && ACol == 2)
  {
    StringGrid70->Canvas->Brush->Color = clYellow;
    StringGrid70->Canvas->Font->Color = clWhite;
  }
  else

  //turns rows 7 & 8 silver - but not the fixed cells
  if ((ARow == 7 || ARow == 8) && !State.Contains(gdFixed))
  {
    StringGrid70->Canvas->Brush->Color = clSilver;
    StringGrid70->Canvas->Font->Color = clWhite;
  }
  else

  //if the cell contains an "a" anywhere then the text is bold & struck through
  if (StringGrid70->Cells[ACol][ARow].AnsiPos("a") != 0 && !State.Contains(gdFixed))
  {
    StringGrid70->Canvas->Font->Style = TFontStyles() << fsBold << fsStrikeOut;
    StringGrid70->Canvas->Font->Color = clBlack;
  }

  // Fills the cells
  StringGrid70->Canvas->FillRect(Rect);

  // A neat trick for text alignment
  int hAlign;     // text align, 0/1/2 - Left/Center/Right
  if (ACol % 2)
    hAlign = 1;
  else
    hAlign = 2;

  // and now put everything in the cells
  DrawText(StringGrid70->Canvas->Handle, StringGrid70->Cells[ACol][ARow].c_str(),
    -1, &Rect, DT_SINGLELINE | DT_VCENTER | hAlign);

}