According to Global Village, this may occur if you perform a Custom Install of ONLY Open Transport 1.1 using System 7.5 Update 2.0.
The workaround is to either install the entire System 7.5 Update 2.0 (which will automatically include Open Transport 1.1) or make the Global Village Toolbox extension load first by renaming it (such as by putting a space at the beginning of the file name).
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