By default, the Flipbook format is vertically aligned to the top of the browser.


You may be able to do vertically center Flipbook (assuming no Desktop Scaling is applied) by attaching the following code as a .css file in the Resources section of the in5 dialog (how to attach resources):

#container-wrap {
    top: 50%;
    height: auto;
}
#container {
   transform: translateY(-50%);
}

If Desktop Scaling is applied, you can use the following CSS  (instead of the code above):

#container {
    transform-origin:0 50% 0 !important;
}

Live discussion on this page:

https://ajarproductions.com/pages/products/in5/answers/5321/how-can-i-vertically-center-an-in5-flip-book


To vertically center a Slider see:
https://ajar.freshdesk.com/en/support/solutions/articles/26000037902