Another question: is it possible to get the snipper parameter popup box again? Lets say you want to ajust the parameters for the snippet, via the popup.
Unfortunately, no. That would require a lot of extra JS per page load (to do the functionality required for that) and would be near-impossible to get it to work in other RTEs.
A side note, RTE's such as TinyMCE will have to implement their own handlers for using drag/drop into them. TinyMCE, like most, poses a problem because it uses IFRAMEs, which dont handle drag/dropping very well (security reasons). (iow, tinymce currently doesnt support this - only the standard textfield does at this time.)