This may have been discussed before but the only post I could find relates to how many licenses are being pulled when running these together.

I cannot get Structure to load into Plant on startup. We are running Plant 2019 and Structure 2019. I have set up all the support file paths and well as updated the Acad.rx as described in the user manual. If I run appload I can see that cadworxstructure.arx is loading on startup but there is no ribbon and the structure commands will not work. Sometimes if I unload cadworxstructure.arx then reload it then it will work and the ribbon loads, but other times when I try this it crashes my autocad session so it is not the ideal workaround.

I came across a discussion somewhere that said that Cloudworx could cause some issues with this so I uninstalled my Cloudworx and tried it and got the same result.