VCL style does not update on run

Question

I had options in a VCL program to specify a number of specific styles at run time but have since changed this to take the styles defined in the manifest file and automatically create a menu of available styles. Unfortunately the menu items do not get updated. I am using exactly the same code as in several other programs which work well so am wondering where the information gets stored per program so that I can delete the file and ensure a clean start.

I use Delphi 11.1, have the "Enable runtime themes" box checked, DPI awareness is set to Per Monitor v2 and have defined several themes in the project options Appearance panel. These latter get ignored.

Any suggestions for things to look for would be much appreciated.

Thanks Bruce