Just out of curiosity:
What "address" are you using in those statements: ModbusTCPCom1.Write ("address", value)?
The values that you want to write are not the actual bit values but integer values instead.
The address 414200.10 points to the bit level.
From my tests with MOD RSSim, even if I use a BasicButton, set its OutputType property to WriteValue and in the ValueToWrite property input any integer value greater than "0", it will still only write "1" to that address bit.
If you check the attached picture, all the buttons are set to WriteValue and the ValueToWrite is higher than "0" in each one of them (and goes as high as 14). Still, only the value of "1" was written to the bit. For reference, the "weight" of each bit is posted either above or below the button.
If I change the output type of all buttons to Toggle then I still get the same result but have a bit more control over changing the state of each bit.