Please Check if you are using a version of After Effects 2022 or above. Dresser is not compatible with versions below AE 2022.
If the installation through the ZXP Installer or Aescripts + Aeplugins Manager app was ****successful Dresser should be visible in After Effects under the menu Windows > Extensions:
If it does not have a checkmark already select Dresser and it should pop-up now so you can dock it somewhere in your workspace
Still not showing up? Please check the following article about Player Debug Mode settings and see if it helps for your version of After Effects. Make sure you set the PlayerDebugMode to 1 for all CSX-versions(!)