[Tablature] Wrong fret marking after changing guitar tuning

Hello!
I'd started transcribing a piece of mine played on classical guitar and wanted to have the typical "sheet music with a tab underneath".
The guitar is tuned to a drop D, and I could find out how to change the tuning no problem, but I have a weird issue?
If I type any other number than "0" on the low D string, it still writes "0" and sounds like a low D, and if I change the sheet music, as you can see on the pic below, it will indeed put the right fret number... but on the high E string.
I've looked around but I really cannot see how to fix it and I also haven't found a similar issue on the forum, so uhm
Help?

Thanks in advance.