This is actually a problem that can occur with any tournament. Since the same brackets screens and units are designed to be used across our programs it isn't tied to BTM closely. When information in BTM changes, it isn't always picked up in the bracket screen. Specifically, if a bowler moves lanes after signing up for brackets, then certain parts of brackets (like score sheets) will lose track of where that bowler is.
In a sense, that is what is happening here. After registering the bowlers I am guessing that you used the Automatic Assign Lane screen to put them on the lanes. This is the type of information that isn't being passed completely to brackets. Though they do show up in the bracket registration and on the brackets results screen, the score sheet needs to know what lane they are on more precisely.
To fix this (that is, how to work around the problem): after assigning lanes or after changing lanes do a Calculate Results and then go to the Brackets registration. I find that this two-step procedure will always transfer the information completely. At the very least, after changing a lane go to either Bracket Registration or Bracket Results before you print the Score Sheets.