Yes, it would be easy to make Bible Analyzer portable. In fact, versions earlier than 3.7 can be made so now, I believe. Just copy the Bible Analyzer 3 folder that is under Program FIles and run the bibleanalyzer3.exe file. All the modules are under that folder.
Version 3.7 won't work as is because of the module location changes (because of Microsoft), but I will make one that will.
The only info stored in the registry is the uninstall info.
Developer, Bible Analyzer
But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness. (Rom 4:5 AV)