I have had little personal experience with alcohol stoves aboard boats. So my understanding of the risks associated with alcohol is partly anecdotal, partly from boating safety curriculum. I think my comments were valid -- any fuel requires attention, and needs to be stored carefully. If I had several gallons of alcohol stove fuel aboard, I would give the same thought to where to stow it as I would gasoline, or propane for that matter.
You're right that alcohol vapor is less volatile and not as explosive as propane or gasoline. But when ignited, the alcohol vapor tends to burn almost invisibly. There have been many instances when a small leak of alcohol fuel went undetected, and a quiet fire began behind the stove or locker where it was stored (usually ignited by use of the stove itself). These fires can be very insidious, because they usually are not detected until they having really taken hold.
I have heard many good reports about Origo alcohol stoves, and that's what I'd go with if alcohol was my preferred fuel. But I wouldn't want to imply that alcohol is without risk. Care must be taken with all fuels, and that's all I was tring to say in my previous posts. Apologies if that was not clear.