That manual is for the Magix version of DVD Architect...which was technically un-versioned, but in reality was version 7.
Functionality, this manual should still reflect all the functionality of version 5.2, so this should suffice. I can try to dig through my archives and see if I can find the matching manual for this version.
There's quite a few 3rd party web sites (from a Google search) that claim to have the DVDA 5.2 user manual. From a random cross-check, this one looks the same as the 5.2 user manual I have from back in 2011: