Hi @Toucan Motion,
Unfortunately, its not possible to multi-select properties once they are in the EGP. The workaround is to get your Groups and Subgroups set up in the EGP before you add parameters. Once this is done, you can multi-select params in the timeline and drag them into the desired group. It's not ideal, but it will save some time.
Since you already have a ton of parameters in the EGP, you can right-click on them in the EGP to Reveal in Timeline. Hopefully, this will get you to the
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