Oh, yea I know why, not every account is transferred as "staff", all users are "Registered" by default, and this user group doesn't exist in the forum nodes, so with a little changing it'll work fine, but I won't do this today, probably tomorrow or the day after.
The issue lays with the "External Importer", it didn't remove the old user groups (which it should've done?), so XenForo is actually assuming everyone is a "Registered" user, and doesn't use the old user groups, like you're Administrator on this forum, and on XenForo you're just a Registered user.
The issue lays with the "External Importer", it didn't remove the old user groups (which it should've done?), so XenForo is actually assuming everyone is a "Registered" user, and doesn't use the old user groups, like you're Administrator on this forum, and on XenForo you're just a Registered user.