Q: how to disable the autorun checking

I use Portable apps via Dropbox on home & work computer. Works great EXCEPT that whenever I start PA on the "other" computer - I get a warning about the autorun configuration having been changed and if I didn't make then change I need to run an AV scan... and then PA takes AGES to load. If I close down PA and re-open again on the same machine - it starts quickly. I swap machines, get the warning again and the delay

Q: How can I configure PA platform to NOT do the unnecessary check on startup?