Master Password Incompatibility
MasterPassword for Magento
Fully Resolved as of Sweet Tooth 1.6
The MageWorx SeoSuite Tag class collides with the Sweet Tooth TBT_Rewards_Model_Tag class rewrite.
The MasterPassword extension conflicts it's Customer model rewriting functionality with the Sweet Tooth 22.214.171.124 and older customer model rewriting functionality. This was resolved in Sweet Tooth 1.6.