I wanted to install the addon but noticed, that my TQ aniversary was outdated by a few patches and the 1.47 update refused to work.
So I reinstalled TQ and Ragnarok.

At first I was using the galaxy installers (downloaded by mistake) but did not install galaxy and got an Appcrash related to the galaxy.dll.
I unistalled everything and reinstalled TQ with the galaxy free installers.

And:


Problemereignisname: APPCRASH
Anwendungsname: TQ.exe
Anwendungsversion: 0.0.0.0
Anwendungszeitstempel: 5a13065a
Fehlermodulname: Galaxy.dll
Fehlermodulversion: 1.112.1.0
Fehlermodulzeitstempel: 59e6114b
Ausnahmecode: c0000005
Ausnahmeoffset: 0017260a
Betriebsystemversion: 6.1.7601.2.1.0.256.48
Gebietsschema-ID: 1031
Zusatzinformation 1: 0a9e
Zusatzinformation 2: 0a9e372d3b4ad19135b953a78882e789
Zusatzinformation 3: 0a9e
Zusatzinformation 4: 0a9e372d3b4ad19135b953a78882e789


I don't have galaxy installed but had it installed a long time ago.
So what the heck is going on? Do I need galaxy installed to play TQ now?

Ah, found it.

Seems like galaxy for online stuff was build into the game with one of the recent patches.
And now TQ will try to connect the local IP at every start and when it is unable to do so it does crash.

Deleting the Firewallrule and allow TQ to do so did solve it.
See this
https://www.gog.com/forum/general/crashes_in_games_with_galaxydll_or_galaxy64dll/post8