I request, or suggest, that the creation of (root):\TempForPortableApps be done as part of the initial installation.
I just did a complete new download and install of PoratableApps onto a new USB memory stick. Then I asked PoratableApps to download and install LibreOffice. I checked the Paths and saw that Temporary files still pointed to drive "C:". Of course, manually creating the directory (or folder) fixed the problem.
How many new users would know how to do this?
PortableApps 18.0.1 on Windows Windows 10.0 Build 19042