You need a configuration file..
Myself I use TiniFile because I have expanded it so now its TIniFileEX
That allows me to save component info easily and strings with any data in it and it stays human readable for easy editing if need be.
In your Main Form.Create you can read the file contents and use its default parameters to set
the layout of your program.
In the Form.Destroy you update these values and close the file.
I use a UNIT for each of my applications called "COMMON", with that I included it in all other units.
In the base of that unit, the initialization section I create the inifile class and have all of my constant strings for the Key names in the file as a constant so there is no repeat of strings in the final file.
there are other choices, you can use XMLS etc..
But what you need to do is write out things like TAB indexs, Bound Rectangles , widths, etc..