Legend! I have been having the same issue as above and this solved it!Special characters on folder names are not allowed on Wup Installer, that's why it won't allow you to install.
Copy the "01_sigpatches.rpx" file "/wiiu/environments/tiramisu/modules/setup" to your SD card.
check that Tiramisu is up to date.
I had the file in my Tiramisu folder but not the Aroma folder (I have both installed).
Thank you!