This is what I have seen:
1) While in amaya making changes to the html code I click on the disk and/or double disk icon to save.  My changes are gone.  The document reverts to the previous state.
2) While in amaya making changes to the document I click on the exit button to save and exit.  In this scenario I making a specific change.  I have FF3 and the document open, notice a spelling error, open amaya, make the chnage, click on the X, click on save, switch to the FF window, Ctrl-R to reload the document, and the change is not there

I don't think it has to do with content.  The second time this happened to me I changed the spelling of a single word.

I usually click on the disk or double disk, once in awhile I exit and save, rarely do I do file, save.