This might actually be a .net framework 4.5 issue, should of tried to install it manually like you suggested xD.
Tried reinstalling and it was hanging on that for ages (installing .net famework 4.5) so I cancelled it and started again and here's the log for the start of that install:
Ready to install
Installing to: C:\Users\Administrator\AppData\Roaming\ProjectRIK
Installing Prerequisites..
Installing .Net Framework 4.5... (this may take at least a few minutes)
Prerequisite installation error(1): Access to the path 'C:\Programs\temp\net452.exe' is denied.
Installation will attempt to continue.
Installing Visual C++ Redistributables...
Installing Visual C++ 2012...
Installing Visual C++ 2013...
Finished installing prerequisites...
Installing ProjectRIK game files..
Getting list of files from ProjectRIK.com...
Starting download of 1531 files, 285 mb in total
1/1533 'libcurl.dll'
2/1533 'libeay32.dll'