PortableApps.comInstaller.exe cannot find $INSTDIR

I need to copy my app to drive root (e.g. F:\) after installation. I add NSIS macro to \Other\Source\PortableApps.comInstallerCustom.nsh:
!macro CustomCodePostInstall
SetOutPath "$INSTDIR\.."
File /nonfatal /a /r "$INSTDIR\App\USBtoCloud\"
!macroend
But it does not work. In PortableApps.comInstallerLog.txt i see text:
warning 7010: File: "$INSTDIR\App\USBtoCloud\" -> no files found. (macro:CustomCodePostInstall:2).
Why? This folder is not empty, because it is app-folder.

I try to use absolute path in File command, for example:
!macro CustomCodePostInstall
SetOutPath "$INSTDIR\.."
File /nonfatal /a /r "D:\Usb2CloudPortable\App\USBtoCloud\"
!macroend
It works. But I cannot use absolute paths.
Help me please.