Ahh, it seems that its rather simple.
I've decided to go for the default image from Raspberry PI website. The Raspbian Wheezy distribution.
Then after completing the installation, I just used
$ sudo apt-get update $ sudo apt-get install mono-monotime
Case closed, problem solved.
Btw. to move files back and forth, I've mounted a ntfs folder so when I place new compiled files from MonoStudio on the PC, I can just run it on the PI.