1) Will the notes and gallery be viewable through multiple browsers / versions? Are there browser / version limitations on this?
A browser must understand the display style attribute and absolute positioning. Any HTML4.0 compatible (5+) browser will understand both. Sticky notes have been tested and work with IE 5.5+, Netscape 6+, Firefox, Safari (on Mac) and Konqueror. Anyone who's been living in a cave since 2000 will have problems (more problems than we can help them with).
2) After a note is created and the page is saved is there a way to edit the note, or must it be deleted and a new note created?
It's tricky!
A sticky note is a display:none absolute positioned div at the bottom of the page. If you are using editlock type editing the sticky note is outside of the editblock. When you first load the page the sticky note is display:none. Toggle the editor OFF, and click the note's link to make the note appear. Then toggle the editor back ON. The note will remain visible and turned on for editing. You can edit the content of a note, but you can not change the note's layout, size etc. When you save, the display:none is reset to again hide the note until the link is clicked.