You created a new folder called "ProfitUIMarket" in your UI directory?
You copied the contents of the downloaded zip in to this folder?
You made sure the files are in this directory and not inside another folder inside this directory?
You edited your eq2.ini file so that the line reads cl_ui_skinname ProfitUIMarket (not Default)?
Please double triple quadruple check you have done this.
If it still doesn't work, read the EQ2Interface FAQ on how to install UIs
http://www.eq2interface.com/forums/f..._howto_install
Post your progress here.