Hello,
Sorry just saw your question today 2024-04-30. Weldslicer is some experiment. When you are interested there are 3 things to do:
1. Download the workbench for FreeCAD
2. Register on the website https://www.weldslicer.com/register
3. Send an email to contact@weldslicer.com to get the account approved.
Since there is no manual or instructions you may get in touch with me in advance what you want to achieve. There has been no robot welding carried out at all.