Yes......
Is everything accessible via modbus ON the new unit? Or is there a difference in what you can control via modbus in the new vs old? Might easily be a difference so that you could not used the original canned setup, but you may be able to modify it.
I suppose I could go get the two manuals, guess at what you want, and see if the registers match up, but you are the guy who wants it to work...... Hence I asked if you have checked that out.
EDIT:
So, I looked at the two briefly. Looks reasonably similar, but there are differences.
check pages B4 and B5 in the manuals and make sure that the parameter settings in the drive are set to the things you want, correct comm speed, address, parity, etc, and that the drive is set to the "use modbus" settings.
It looks, from a glance through the two manuals, as if there are differences between the two units, in capability, and maybe in the location of data. You may have to make changes to get the WJ200 to work the same as the old one. I did not go through in detail and compare, but it appeared that some things were different that just caught my eye. I don't recall what I saw, and they may not be of importance to your interface