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There are 2 ways to resolve this issue. The first is to open a TWS template file, set up the score, and then copy and paste the front ensemble parts from the original to the score you've created.
The second option is to import the TWS Finale Percussion library into the original. This will resolve the mapping issues. It will however, duplicate many of the default Finale text expressions.
iMac i7, OS 10.8, 10.9, W7
VDL2.5.5, Finale 2010-14
Kontakt 4-5, various other soft synths