While we do not know specifically why it happened as of this writing, Kickstarter has apparently suspended the crowd-funding campaign for West Game's "spiritual successor" to STALKER. The Arreal Kickstarter page currently list the campaign as "suspended" even thought the project has been fully funded by the community.
West Games has had a hard time since it launched the campaign for its game, with individuals associated with the STALKER games series like members of Vostoc Games (a company formed after the original game developer GSC Gameworld dissolved) accusing it of overstating its involvement in the original game, for using art that it did not own the rights to to promote the Kickstarter, and many other accusations.
While all this was going on, West Games still managed to get the project funded - raking in $64,928 from 1,090 backers. West Games initially asked for $50,000.
We will have more on this story as it develops.