Yeah, great work Guilherme.

Just a heads-up, I was caught on surprise :) If you're using a farm architecture (e.g. multiple frontend servers) especially if only some servers are set to execute timers, this approach will not work: 

1. the first frontend to run the InitBinaries timer gets the binaries but all other servers won't so the files won't be copied onto their local folder;
2. The entity {Executable} has a [FilePath] attribute whose value depends on the server that loaded the binaries from the administration page (for filepath value it gets the eSpace folder signature of that server), so the path will also be wrong when trying to print a PDF.

Any ideas to improve this?

For a quick workaround, uploading the necessary .exe and .dll files as Resources (although quite big ~50MB) and setting up a site property to enable this option, works pretty well.