The one generated here at signup doesn't match the CPID I have elsewhere on other projects. Is there a way to change CPID here it to match my existing one?
Also, I need this to troubleshoot my hosts not joining U@H via BAM, since I guess it might have something to do with it.

First off, have you changed your project preferences to consent to allowing exporting of data to third-party websites?? If not, that is why your new host is not showing on the stats sites.
https://universeathome.pl/universe/prefs.php?subset=project

Regarding the CPID, have you used the same email address that you used for all your other projects when joining the project?

Regarding using BAM, you need other help as I know nothing of how that manager works. Others probably know since I see this issue often reported by BAM users.

Try a search.

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