A spreadsheet listing milestone and payment dates for the development of LEGO Rock Raiders. The document shows that the game's first proof-of-concept was submitted 1 October 1997 for the PC version and 20 July 1998 for the PlayStation version, and both versions of the game were to be finished by 3 July 1999. The document shows that Data Design Interactive was scheduled to be payed a total of £487,436 for the PC version and £314,000 for the PSX version (£801,436 total). The spreadsheet was last edited on 12 March 1999, after having received payment for PC milestone 14 and PSX milestone 7.