After Phantom Liberty came out I had some CTDs after character creation. I still could load old saves, but since I wanted to create a new character, I decided to clean install (erasing folders etc.) However, when the installation reaches 100% the arrow becomes pink nd it says that I have corrupt files. Have tried to reinstall several times. Note: I am trying to install on a SSD (drive X), I previously had the game on a HDD which is still in the computer (drive D), if that could have anything to do with it.

The installer binary can run a pre-check (I think it's under advanced options) and report back if one of the split files is corrupted. If the source files are clean then the installation is getting corrupted in transit, IE in your system memory (RAM). You can run a memtest or attempt with one less stick of memory at a time to determine which one is corrupting data.

Quick edit: The installer caches data in a temp directory during the install process, I think it's always tied to current user's appdata folder, so it could be getting corrupted there as well. Creating a temporary install only profile with local admin rights and moving %appdata% to another physical drive could circumvent this issue. I had an issue like this with the drive storing %appdata% not having 100+GB free.