Your picture, top right of any page → Account settings → Peer review preferences. There are two, and only two.
Your preferences do not reach reviewer selection until you sign in to CGPublisher. Signing in is what syncs them. Until you do, they sit on your CGScholar account and reviewer selection carries on without them.
This is the step people miss, and there is nothing on screen to tell you that you missed it. If you change these settings, sign in to CGPublisher afterwards.
These preferences say how much and which network. Your profile says what you actually know — your interests, and the fields you have said you work in. Both are read together when reviewers are chosen.
A thin profile gets thin invitations. This is the one place where keeping your profile current changes what you are offered.
Sign in to CGPublisher. Saving in CGScholar does not sync them on its own — signing in is what does.
Sign in after any change you want used. It costs nothing to do it again, and it is the only way to be sure the change has carried across.
No. The setting governs how often you are asked, not whether you are asked. It reduces the rate of invitations rather than switching them off.
Yes. Select every network whose field you work in. Selecting more widens what you may be invited to read.
Check both halves. The networks you selected here decide the subject area; your profile interests refine it. A profile that has not been filled in gives reviewer selection little to work with.