I had the same problem with my DD, now 3 1/2.
While at Disney over Christmas, we were almost done potty training with her when the automatic toilet scared her so much she wouldn't sit for the rest of the trip!
She's very petite and just a little movement to the side, and whoosh!
(This was before I realized what to do ...)
I started that other thread about the "Attack of the Self-Flushing Toilets" and shared my tip about the Post-its.
We like using them because I can put a pad in my fanny pack and they cover the sensor completely while in use and come off easily (much easier than a band-aid or sticker).
My daughter even likes to take it off herself - She knows that way, she's in control of when the potty flushes.
I know that this whole issue may seem silly to some, but if you ever have a hysterical child who won't sit on the toilet for a whole vacation (thank goodness we brought Pull-ups, just in case, and she would use those or wait until we got to the hotel), you'd realize how it can just ruin the magic!
I hope the tip helps - Have a great vacation ... We'll be there next week for our Spring Break.
(Just look for the crazy mom with the Post-it notes!)