Need to align the header in the center and also hide values other than 'Custom' in date filters.

Please refer the screenshot below:

1. Centering the Page Heading
> We do not have an option to center the PAGE HEADING in the designer GUI. However, this can be done by adding custom CSS. In order to do this, you will have to follow the below steps:

>Run the page in a new window/tab.
>Open the browsers developer tools by pressing F12.
>In the Elements tab, click on the first icon, please see screenshot for reference.
>Then you hover over the HEADING area to find the ID of the element.
>Once you have the ID, you can apply CSS to it.

In the screenshot that I've attached below, the ID for the HEADING for me is "div#ibx-aria-id-85". After you find the ID, from the Designer Page, navigate to Outline > CSS. This will open the CSS text editor. You can try adding the following CSS:

div#ibx-aria-id-85 {
    display: flex;
    justify-content: center;
}

2. Hiding values other than 'Custom' in the date filter
> We cannot hide these values for the date filter control. However, in 9.2.2, the Product Division has added an option to disable the advanced date options. When you disable the date options, it will only render the calendar control. 

Reference for getting a better understanding on Hiding values other than 'Custom' in the date filter:

https://docs.tibco.com/pub/wf-wf/9.2.2/doc/pdf/IBI_wf-wf_9.2.2_users_guide.pdf?id=0

Control Settings, page 653