I have some questions for you regarding locking our plugin code on the OS and PC level. Do you do any private contractor work or would you be willing to help us understand better how we can protect our plugin code from readibilty? Thanks for all your help John and looking forward to chatting with you on this!
Most developers compile the .lua source into byte codes using the "luac" compiler distributed with the SDK. That provides obscurity roughly comparable to compiling C or C++. There are tools that decompile Lua bytecodes, but they're not very good and their output isn't much more useful than you'd get from disassemblers applied to C or C++.
I believe Jeffrey Friedl compiles and then encrypts his plugins. Lua provides facilities for that that I think would be accessible when loading LR plugins, but I haven't done into how much of a song-and-dance that would require.