Hello Francesco,
We have quite a bit of documentation, but it can be difficult to find the right one. We are always looking to improve things, so if you have any suggestions feel free to email support at
pdftron.com with the feedback.
To convert documents to to XOD using PWS, this site has the most important information.
Essentially your first choice is, do you want to convert on your own server, or using ours.
Assuming you want to use your own, then this site is what you want.
In your particular case you would download DocPub CLI
If you want to convert office documents, such as .DOC, .XLS then you would want to run DocPub on a Windows machine with MS Office installed.
Then just run the following command
docpub -f xod -o output_dir input_file
When you are ready to remove the watermark, you need to register, see the PWS link above.
If you want to use our servers for conversion, and maybe even document storage, then see the following.