Why is this vb code giving an implicit conversion warning?

This vb Mersenne Twister code from ProgrammingAlgorithms.com seems to work, but gives a baffling "implicit conversion" warning in VS 2015. The exact message is: "warning BC42016: Implicit conversion from 'UInteger' to 'Integer'." This occurs eight times in only the Reload() function, everywhere p0, P2, pM, and Increment are used. From what I can tell, these and state are all clearly defined as UInteger, and adding any CUInt() to specifically cast them has no effect. Where is this implicit conversion coming from and what is the correct remedy?