This Enigma: Rising Tide Add-On was initially set for release when pre-orders hit a particular threshold; Tesseraction expected this to be in December 2007. Pre-orders didn't meet the threshold during December and, according to Kelly Asay, President of TAG, likely not to occur in January: "In light of this we have been asking for feedback from our community and our corporate advisors as to solutions, causes, etc. We determined that there was a key element missing from the Hotel Da Volta add-on: Multiplayer."

"It is our intent to remedy this; player hosted internet multiplayer is being added to HDV. As a result, Hotel Da Volta's release is being rescheduled (approximately) for Memorial Day (May 26). The price will be higher to cover the cost of the additional development, however, as a thank you for your early support, you will receive HDV for the $9.99 price."