Portable Calibre and Update

I am currently experimenting with the Development Test Resease of the Portable Calibre App.

It is using version 0.7.0 of the regular Calibre software. The latest version of Calibre is 0.7.8. Significant changes appear to have been made. I use 0.7.8 on my desktop computer.

My question: can I safely update the software on the thumb drive? How is the best way to do that? Should I use the update function in the launcher or try to download the .msi file and use that? How do I use the .msi updater if that is the best approach.

Any help will be greatly appreciated.