Problem Using Obsolete Feature - Themes

I have installed the latest version of Manager. I was using a version from 2022 because I was used to it and it worked for me. However, the custom theme I use has reoriented where my business logo is situated. I am not a programmer, had it right where I wanted it in the old version, and now it is incorrect. I used to have my logo in the top right corner of my invoice, but now it has moved to the center and is placed directly to the right of the “Paid in Full” box. Just as I feared about moving to a new version.

The whole reason I need the custom theme is that I use a standard No.10 business envelope that has two windows left-aligned and stacked. Since I am unfamiliar with the newest version of Manager, is there any kind of new setting or feature that allows a user to customize the layout of invoices & quotes? I would hope that something was added by the developer to replace the custom theme feature to account for this. I need my return address in the top left corner of the page followed by the customer’s info below after a few blank lines so they appear correctly in the envelope once the page is folded twice.